vol_14 - Polskie Towarzystwo Promieniowania Synchrotronowego

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vol_14 - Polskie Towarzystwo Promieniowania Synchrotronowego
CONTENTS
XIth KSUPS — information
V
News from SOLARIS – the first Polish Synchrotron
VII
PROGRAMME
VIII
Welcome to the 11th KSUPS
X
J. Szlachetko
Electronic structure of matter probed under in-situ
conditions by means of X-ray spectroscopy techniques
L-01
1
T. Tyliszczak
Soft X-ray Absorption Spectroscopy – Chemical Analysis
on nanoscale
L-02
4
I.N. Demchenko
Elemental and orbital-selective characterization of
semiconductor materials by X-ray spectroscopy - XAS,
RIXS and XPS
L-03
5
A. Burian, R. Babilas, A. Fitch,
L. Temleitner
Wide-angle X-ray scattering and Reverse Monte Carlo
studies of Fe80B20, Co80B20, Mg60Cu30Y10 metallic glasses
L-04
8
L. Vasylechko, O. Pekinchak,
O. Pavlovska, R. Stepchuk, Yu. Prots,
D. Chernyshov
Structural, electronic and magnetic phase transitions in
complex oxide perovskites probed by X-ray synchrotron
powder diffraction
L-05
9
Cz. Ślusarczyk
Badanie w czasie rzeczywistym procesu krystalizacji
polietylenu przy zastosowaniu rozpraszania
promieniowania synchrotronowego pod małymi kątami
L-06
10
A. Drzewiecka-Antonik, M.T. Klepka,
A. Wolska, P. Rejmak
Structural studies of metal-organic ligand complexes
using X-ray absorption spectroscopy
L-07
13
J. Cebulski, E Sheregii, J. Polit ,
A. Kisiel, A. Marcelli, B.V. Robouch,
M. Piccinini
Study of phonon spectra of (Cd,Hg)Te-based
semiconductor solid solutions using synchrotron radiation
L-08
14
W. Gawelda
Status and science program of the European XFEL
L-09
15
R. Sobierajski
Phase transitions in solids under irradiations with X-ray
free electrons lasers – characteristic time scales
L-10
16
M. Waśniowska, M. Sikora,
M. Dobrzański, I. Miotkowski, T. Eelbo,
Z. Kąkol, A. Kozłowski
Magnetic impurities in the bulk and on the surface of 3D
topological insulators probed using soft X-ray
spectroscopy
L-11
17
M. Kręglewski
High Resolution Molecular Spectroscopy using
synchrotron light source
L-12
18
J. J. Kolodziej, K. Szamota-Leandersson
UARPES -Angle Resolved Photoelectron Spectroscopy
beamline at National Synchrotron Radiation Centre
SOLARIS
L-13
19
P. Starowicz, R. Kurleto, J. Goraus,
H. Schwab, M. Szlawska, F. Forster,
A. Szytuła, I. Vobornik, D. Kaczorowski,
F. Reinert
Momentum dependence of a Kondo Resonance
in Ce2Co0.8Si3.2
O-01
20
Y. Melikhov, J. Sadowski,
P. Konstantynov, M. Chernyshova,
J. Domagala, T. Wojciechowski,
I. N. Demchenko
Structural evolution of (Ga,Mn)As thin film during medium
temperature post growth annealing manifested by XAS
O-02
21
M. Pławecki
Fabrication and characterization of multilayer solar cells
O-03
22
I
J. Kubacki, D. Kajewski, A. Koehl,
Ch. Lenser,R. Ditmann, J. Szade
Application of X-ray absorption and resonant
photoemission spectroscopy to study electronic states
O-04
23
of iron through 3p-3d transition for SrTiO3:Fe epitaxial film
H. Fiedorowicz, A. Bartnik,
P. W. Wachulak, R. Jarocki, J. Kostecki,
M. Szczurek, D. Adjei, I. U. Ahad,
M. G. Ayele, T. Fok, A. Szczurek,
A. Torrisi, Ł. Węgrzyński
Laboratory sources of soft X-rays and extreme ultraviolet
(EUV) based on laser plasmas produced with a gas puff
target
O-05
24
D. Paliwoda, M. Hanfland
Single-crystal X-ray diffraction at extreme conditions
O-06
27
J. B. Pełka
High-brilliance X-ray sources: a bright future for life
science studies
O-07
28
M. Kozak, Z. Pietralik, M, Taube
SAXS studies of selected flexible proteins or proteins of
modular structure
O-08
28
M. Taube, A. Jarmołowski, M. Kozak
Solution structure of the plant HSP90-SGT1 complex
with ADP
O-09
30
W. Gospodarczyk*, M. Kozak
Influence of microfluidic flow on amyloid aggregation of
hen egg white lysozyme
O-10
31
R. Mroczka, A. Sykuła, E. A. Stefaniak
Micro-X-Ray fluorescence spectrometer with X-ray single
bounce metallic capillary optics for light element analysis
O-11
32
P. Goryl, C. J. Bocchetta, Ł. Dudek,
P. Gałuszka, W. Kitka, P. Kurdziel,
M. Ostoja-Gajewski, R. Różańska,
M. J. Stankiewicz,
K. Szamota-Leandersson, J. Szota,
T. Szepieniec, T. Szymocha,
A. I. Wawrzyniak, K. Wawrzyniak,
M. Zając, Ł. Żytniak
Solaris control and IT systems towards beamline users
O-12
33
A. Thissen, S. Bahr, T. Kampen,
O. Schaff
New developments in small spot and imaging Near
Ambient Pressure XPS
S-01
33
B. A. Orlowski, E. Guziewicz,
B. J. Kowalski, A. Reszka
Synchrotron radiation photoemission study of doped
semiconductors valence band
P-01
34
R. Minikayev , E. Dynowska,
A. Szczerbakow, A. M. T. Bell ,
W. Szuszkiewicz
The limit of CdTe solubility in PbTe and the phase diagram
of (Pb,Cd)Te solid solution
P-02
34
R. Rapacz, K. Balin, M. Wojtyniak,
J. Szade
Atomic and electronic struture of Bi-Te films grown at
various conditions by MBE method
P-03
36
W. Paszkowicz, J. López-Solano,
P. Piszora, B. Bojanowski, A. Mujica,
A. Muñoz, Y. Cerenius,
S. Carlson, H. Dąbkowska
Compressibility and electronic structure variation with
pressure for EuVO4: A combined experimental and
computational study
P-04
37
P. Solarz
Energy transfer processes to Eu3+ ions in K5Li2GdF10
doped with Eu3+, Pr3+, Tb3+ and Dy3+ upon VUV excitation
P-05
37
A. Bajorek, G. Chełkowska
Electronic structure of selected ternary samarium
compounds
P-06
39
A. Wolska, M. T. Klepka, I. Sveklo,
A. Wawro, A. Bartnik, P. Mazalski,
R. Sobierajski, J. Fassbender,
A. Maziewski
Local structure around Co atoms in the ion and light
irradiated magnetic trilayers
P-07
42
II
D. Klinger, I. Jacyna, J. B. Pełka,
A. Reszka, E. Łusakowska, A. Wawro,
M. Jakubowski, A. Bartnik, R. Sobierajski
Morphological and structural modifications induced in
ultrathin metallic films by nanosecond pulses from EUV
laser-plasma source.
P-08
43
I. Jacyna, D. Klinger, J. B. Pełka,
R. Sobierajski, P. Dłuzewski,
M. T. Klepka, E. Dynowska, A. Wawro,
A. Wolska, M. Jakubowski, A. Bartnik,
I. Sveklo, Z. Kurant, D.Eichert,
I. Makhotkin, S. Yakunin, A. Maziewski
Investigation of morphological and structural changes in
ultrathin Pt/Co/Pt trilayers induced by nanosecond pulses
from EUV plasma source
P-09
44
E. Dynowska, A. Marynowska,
L. T. Baczewski, J. Fassbender,
R. Böttger
Structural properties of Fe/Pt multilayers before and after
ion beam irradiation
P-10
45
M.T. Klepka, A. Wolska,
A. Drzewiecka-Antonik, P. Rejma,
G. Aquilanti
XANES and EXAFS studies of bioactive metallo-organic
complexes in solid and liquid state
P-11
46
K. Lawniczak-Jablonska, A. Chruściel
XAFS estimation of the catalytic centre in double metal
cyanide catalysts
P-12
47
Ż. Kołodziejska, Z. Pietralik, M. Kozak
Trimeric surfactants – new effective carries for gene
therapy
P-13
49
M. Skupin, Z. Pietralik, K. Sobczak,
R. Zieliński, M. Kozak
Structural studies of nanosystems based on zwitterionic
sugar-based surfactants as innovative gene delivery
systems
P-14
50
W. Andrzejewska, M. Skupin, M. Kozak
Studies of dsDNA and siRNA oligomers in complexes with
tricationic surfactants using biophysical methods
P-15
51
M. Kręcisz, J.D. Rybka, S. Haracz,
A. Strugała, I.Zhukov, A. Urbanowicz,
M. Figlerowicz, M. Kozak, M. Giersig
Physical characterization of BMV capsid protein
P-16
52
M. A. Śmiałek, M. Łabuda, J. Guthmuller,
S. V. Hoffmann, N. C. Jones,
M. A. MacDonald, L. Zuin,
M. -J. Hubin-Franskin, J. Delwiche,
D. Duflot, N. J. Mason, P. Limão-Vieira
Valence and ionic lowest-lying electronic states of small
esters studied by high resolution vacuum ultraviolet
photoabsorption, photoelectron spectroscopy and ab
initio calculations
P-17
53
Z. Pietralik, A. Szymańska, M. Kozak
Spectroscopic characterization of human cystatin C and
its mutants
P-18
54
T. J. Wasowicz, A. Kivimaki, M. Coreno,
M. Zubek
Hydrogen migration in formation of NH(A3Π) radicals in
photodissociations of isoxazole and pyridine molecules
P-19
54
K Żebrowska, M. Bagińska, M. Wojdyła,
E. Salas-Colera, P. Zajdel
Local electronic and crystal structures of FeTe doped with
cobalt
P-20
56
M. Bagińska, M. Wojdyła, K Żebrowska,
I. -L. Liu, N. P. Butch, P. Zajdel
Two step transition and suppression of monoclinic
distortion in FeTe doped with nickel
P-21
57
M. Wojdyła, K. Żebrowska, M. Bagińska,
E. Salas-Colera, P. Zajdel
Local electronic and crystal structures of FeTe doped with
nickel
P-22
58
P. Piszora, J. Darul, C. Popescu,
F. Fauth
Li0.95Mn2.05O4 under high pressure and at elevated
temperature in DAC
P-23
59
K. Szutkowski, Z. Pietralik, M. Kozak
The dynamics of micellization of gemini imidazolium
surfactants studied by NMR, FT-IR and SR-SAXS
P-24
60
III
Regular contribution
A. Kisiel
Działalność Naukowa Pracowni Spektroskopii Optycznej
Półprzewodników Instytutu Fizyki Uniwersytetu
Jagiellońskiego. Udział w badaniach z zastosowaniem
promieniowania synchrotronowego
61
Future conferences and workshops
73
Presenting Authors’ Index
75
IV
XI Krajowe Sympozjum Użytkowników
Promieniowania Synchrotronowego
1-4.09.2015, Chorzów
Organizowane przez Polskie Towarzystwo Promieniowania
Synchrotronowego, Uniwersytet Śląski oraz Narodowe Centrum
Promieniowania Synchrotronowego SOLARIS
KOMITET NAUKOWY I PROGRAMOWY
LOKALNY KOMITET ORGANIZACYJNY
Maciej Kozak Poznań
Jacek Szade Katowice
Radosław Przeniosło Warszawa
Zbigniew Kaszkur Warszawa
Wojciech Kwiatek Kraków
Wojciech Paszkowicz Warszawa
Krystyna Jabłońska Warszawa
Agnieszka Witkowska Gdańsk
Bogdan Kowalski Warszawa
Paweł Piszora Poznań
Marek Stankiewicz Kraków
Jacek Szade
Jerzy Kubacki
Marek Kulpa
Anna Bajorek
Katarzyna Balin
Mateusz Dulski
Anna Nowak
Rafał Rapacz
Mateusz Weis
V
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Honorowy patronat
Prezydent Miasta Chorzów
Prezydent Miasta Zabrze
Dziekan Wydziału
Matematyki, Fizyki i Chemii
Dyrektor
Instytutu Fizyki
im A. Chełkowskiego
Dyrektor
Śląskiego Międzyuczelnianego
Centrum Edukacji i Badań
Interdyscyplinarnych
Sponsorzy
Organizatorzy
Polskie Towarzystwo Promieniowana Synchrotronowego wraz z Uniwersytetem Śląskim
oraz Narodowym Centrum Promieniowania Synchrotronowego SOLARIS organizuje
XI Krajowe Sympozjum Użytkowników Promieniowania Synchrotronowego.
Polskie
Towarzystwo
Promieniowania
Synchrotronowego
Uniwersytet Śląski
W Katowicach
Narodowe Centrum Promieniowania
Synchrotronowego SOLARIS
VI
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
News
from SOLARIS – the first Polish Synchrotron
Mamy już pierwsze światło w synchrotronie
Emilia Król*
Narodowe Centrum Promieniowania Synchrotronowego
SOLARIS, ul. Czerwone Maki 98, 30-392 Kraków
*e-mail: [email protected]
Dnia 19 czerwca 2015 r. w synchrotronie Solaris po
raz pierwszy zakumulowano wiązkę elektronów
i przy wyjściu do linii badawczych zaobserwowano
pierwsze światło. Aktualnie wiązka krąży w
pierścieniu przez ponad godzinę. Energia wiązki
elektronowej wstrzykiwanej do pierścienia to 490
MeV, natomiast zakumulowany prąd to 11 mA.
Rysunek 2. Elektromagnesy pierścienia akumulacyjnego Solaris.
(fot. zespół Solaris)
Następny etap prac to powolne zwiększanie
zakumulowanego prądu, aż do uzyskania wartości 500
mA. Jest to proces długotrwały, gdyż układy wysokiej
próżni w akceleratorze muszą zostać odpowiednio
wykondycjonowane. Polega to na stopniowym
zwiększaniu wartości prądu i jednoczesnym oczekiwaniu
na poprawę warunków ultra wysokiej próżni, gdyż
obecnie przy każdorazowym wzroście prądu wzrasta
również ciśnienie w komorach. Proces ten wpływa
również na czas życia wiązki elektronowej. Obecnie czas
życia jest zdominowany przez rozpraszanie elektronów
na cząsteczkach gazu. Jednak wraz z poprawą warunków
próżni czas ten będzie się wydłużać.
Kolejnym zadaniem i wyzwaniem jest uzyskanie
pełnej energii wiązki, która będzie trzy razy wyższa niż
aktualna i osiągnie 1,5 GeV. To działanie również jest
pracochłonne, bowiem przy poszczególnych energiach
należy zawsze korygować optykę wiązki.
Kiedy osiągniemy już stabilną wiązkę o energii
końcowej, rozpocznie się kondycjonowanie i adjustacja
elementów optycznych dwóch linii pomiarowych
PEEM/XAS i UARPES.
Rysunek 1. Obraz wiązki fotonów zaobserwowany na
monitorze fluorescencyjnym przy wyjściu do linii badawczej
PEEM (energia elektronów w pierścieniu 490MeV, prąd 5.2
mA).
(fot. zespół Solaris)
Wiązkę światła udało się zarejestrować za pomocą
monitora fluorescencyjnego, który składa się z płytki
miedzianej, na którą napylona jest warstwa materiału
fluorescencyjnego oraz kamery CCD połączonej
ethernetowo z komputerem. W celu zarejestrowania
obrazu wiązki fotonów, monitor umieszcza się w jej
torze.
Emitowane
fotony
promieniowania
synchrotronowego uderzają w monitor i tym samym
pobudzają go do świecenia, a obraz ten rejestrowany za
pomocą kamery, jest obserwowany w pokoju sterowania.
Wielokrotnie musieliśmy korygować ustawienia różnych
parametrów synchrotronu, w szczególności dopasować
wartości pól magnetycznych wszystkich magnesów do
aktualnej energii wiązki elektronowej, tak aby bez
problemów mogła ona wykonać pierwszy i kolejne
przebiegi po pełnym obwodzie pierścienia – wyjaśnia dr
Adriana Wawrzyniak – główny fizyk akceleratorowy w
Solaris.
Kolejnymi działaniami było zsynchronizowanie magnesu
impulsowego z momentem wstrzykiwania wiązki w taki
sposób, aby efektywnie wprowadzał on elektrony na
poprawną orbitę oraz dopasowanie parametrów wnęki
rezonansowej, by umożliwić ich akumulację w
pierścieniu synchrotronu – uzupełnia Adriana
Wawrzyniak.
Rysunek 3. Synchrotron Solaris.
(fot. M. Domański)
Budowa synchrotronu realizowana jest przez Narodowe
Centrum Promieniowania Synchrotronowego SOLARIS przy
Uniwersytecie Jagiellońskim w imieniu polskiego środowiska
naukowego.
Projekt finansowany jest ze środków Europejskiego Funduszu
Rozwoju Regionalnego w ramach Programu Operacyjnego
Innowacyjna Gospodarka na lata 2007-2013.
VII
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
PROGRAMME
Tuesday, 1 September 2015
800-900
Registration and Reception
900-940
Opening Address
940-1020
L-01
J. Szlachetko
Electronic structure of matter probed under in-situ conditions by means of
X-ray spectroscopy techniques
1020-1100
L-02
T. Tyliszczak
Soft X-ray Absorption Spectroscopy – Chemical Analysis on nanoscale
1100-1140
Coffe Break
1140-1200
O-01
P. Starowicz
Momentum dependence of a Kondo Resonance in Ce2Co0.8Si3.2
1200-1220
O-02
Y. Melikhov
Structural evolution of (Ga,Mn)As thin film during medium temperature post
growth annealing manifested by XAS
1220-1240
O-03
M. Pławecki
Fabrication of characterization of multilayer solar cells
1240-1300
O-04
J. Kubacki
Application of X-ray absorption and resonant photoemission spectroscopy
to study electronic states of iron through 3p-3d transition in SrTiO3:Fe
epitaxial film
1300-1420
Lunch
1420-1500
L-03
I.N. Demchenko
Elemental and orbital-selective characterization of semiconductor materials
by X-ray spectroscopy - XAS, RIXS and XPS
1500-1540
L-04
A. Burian
Wide-angle X-ray scattering and Reverse Monte Carlo studies of Fe80B20,
Co80B20, Mg60Cu30Y10 metallic glasses
1540-1620
Coffe Break
1620-1640
O-05
H. Fiedorowicz
Laboratory sources of soft X-rays and extreme ultraviolet (EUV) based on
laser plasmas produced with a gas puff target
1640-1700
S-01
A. Thissen
New developments in small spot and imaging Near Ambient Pressure XPS
1720-2100
Welcome Party
Wednesday, 2 September 2015
900-940
L-05
L. Vasylechko
Structural, electronic and magnetic phase transitions in complex oxide
perovskites probed by X-ray synchrotron powder diffraction
940-1020
L-06
Cz. Ślusarczyk
Badanie w czasie rzeczywistym procesu krystalizacji polietylenu przy
zastosowaniu rozpraszania promieniowania synchrotronowego pod małymi
kątami
1020-1040
O-06
D. Paliwoda
Single-crystal X-ray diffraction at extreme conditions
1040-1100
O-07
J. Pełka
High-brilliance X-ray sources: a bright future for life science studies
1100-1140
Coffe Break
1140-1220
O-08
M. Kozak
SAXS studies of selected flexible proteins or proteins of modular structure
1220-1240
O-09
M. Taube
Solution structure of the plant HSP90-SGT1 complex with ADP
1240-1300
O-10
W. Gospodarczyk
Influence of microfluidic flow on amyloid aggregation of hen egg white
lysozyme
1300-1420
Lunch
1420-1500
L-07
A. Drzewiecka-Antonik
Structural studies of metal-organic ligand complexes using X-ray
absorption spectroscopy
1500-1540
L-08
J. Cebulski
Study of phonon spectra of (Cd,Hg)Te-based semiconductor solid solutions
using synchrotron radiation
1540-1600
Coffe Break
1600-1800
Poster Session
1800-1930
General Assembly of the Polish Synchrotron Radiation Society
VIII
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Thursday, 3 September 2015
900-940
L-09
W. Gawełda
Status and science program of the European XFEL
940-1020
L-10
R. Sobierajski
Phase transitions in solids under irradiations with x-ray free electrons
lasers – characteristic time scales.
1020-1040
O-11
R. Mroczka
Micro-X-Ray fluorescence spectrometer with X-ray single bounce metallic
capillary optics for light element analysis
1100-1140
Coffe Break
1140-1220
L-11
M. Sikora
Magnetic impurities in the bulk and on the surface of 3D topological
insulators probed using soft X-ray spectroscopy
1220-1300
L-12
M. Kręglewski
High Resolution Molecular Spectroscopy using synchrotron light source
1300-1420
Lunch
1420-1600
Visiting the Silesian Center for Education and Interdisciplinary Research
1600-1640
L-13
J. Kołodziej
UARPES -Angle Resolved Photoelectron Spectroscopy beamline at National
Synchrotron Radiation Centre SOLARIS
1640-1700
O-12
P. Goryl
Solaris control and IT systems towards beamline users
1700-1740
Coffe Break
1800-2000
Conference Excursion
2000-2200
Conference Dinner
Friday, 4 September 2015
830-1140
Excursion to SOLARIS – the Polish National Synchrotron Radiation Center
1000-1140
L-14
1140-1200
Coffe Break
1200-1340
SOLARIS Discussion Panel
1340-1400
Closing Remarks
1400-1500
Lunch
1500-1600
Return to Chorzów
M. Stankiewicz
Prezentacja synchrotronu SOLARIS
IX
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Witamy na XI Krajowym Sympozjum Użytkowników Promieniowania Synchro-tronowego (KSUPS), które
tym razem odbywa się w Śląskim Międzyuczelnianym Centrum Edukacji i Badań Interdyscyplinarnych
w Chorzowie.
Szczególny charakter tegorocznego spotkania jest związany z uzyskaniem kilka tygodni temu
pierwszego światła w Narodowym Centrum Promieniowania Synchrotronowego SOLARIS w Krakowie.
Pierwsze promieniowanie synchrotronowe wytworzone w Polsce to efekt wieloletnich starań i procesu,
w którym ogromną rolę odegrało Polskie Towarzystwo Promieniowania Synchrotronowego, a w fazie
budowy Uniwersytet Jagielloński. To bardzo ważny moment zwłaszcza dla polskiego środowiska naukowców
wykorzystujących to promieniowanie. Wszyscy chcemy, aby polski synchrotron umożliwiał wykonywanie
badań na najwyższym poziomie naukowym. Dlatego tak ważne jest nasze spotkanie w Chorzowie i Krakowie,
w trakcie którego przewidziano szereg wykładów przeglądowych, podsumowujących aktualne osiągnięcia
naukowe, technologiczne oraz trendy rozwojowe z zakresu badań wykorzystujących promieniowanie
synchrotronowe. Ten dydaktyczny aspekt konferencji jest szczególnie ważny dla młodych naukowców,
studentów studiów magisterskich czy słuchaczy studiów doktoranckich, jako potencjalnych użytkowników
polskiego synchrotronu. Równie istotna jest możliwość wymiany doświadczeń pomiędzy młodymi
pracownikami nauki i doświadczonymi wykładowcami. Niektóre prezentacje zostaną wygłoszone przez
pochodzących z Polski naukowców pracujących obecnie na światowych synchrotronach czy też europejskim
laserze XFEL. Liczymy też na ich udział w dyskusji na temat następnych, po obecnie uruchamianych, liniach
badawczych w SOLARIS-ie. Dyskusja jest przewidziana w programie wizyty w Krakowie w ostatnim dniu
Sympozjum, ale będzie pewnie będzie miała miejsce w trakcie całej konferencji. Wierzymy, że efektem
konferencji będzie dalsza integracja środowiska użytkowników promieniowania synchrotronowego w Polsce
i wzmocnienie zaplecza dla badań przy jego wykorzystaniu.
Po raz pierwszy KSUPS ma miejsce na Górnym Śląsku. To znamienne, że ten Region stopniowo
zmienia swoje oblicze i stawia na rozwój edukacji i nauki, czego świetnym przykładem jest miejsce naszego
Sympozjum – Śląskie Międzyuczelniane Centrum Edukacji i Badań Interdyscyplinarnych w Chorzowie.
Witamy serdecznie Uczestników Sympozjum i życzymy dużo dobrych naukowych i nie tylko wrażeń.
Komitet Organizacyjny XI KSUPS
X
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-01
Extended abstract
Tue. 01. 09., 0940-1020
Resonant X-ray emission spectroscopy RXES, relies
on second-order interaction of photon with core
electrons. By tuning the incidence beam energy around
an absorption edge of element, the unoccupied electronic
states are probed via dipole-allowed transitions leading to
intermediate atomic state. The following decay from
intermediate to final state is accompanied by the
emission of an X-ray. Thus the RXES technique is based
on monitoring, at high energy resolution, the intensity of
incoming/emitted
X-ray
radiation
versus
incoming/emitted X-ray energies.
Recently at SuperXAS beamline of Swiss Light
Source we developed a dispersive-type spectrometer [4]
that allowed us to extend the RXES spectroscopy into the
real time-resolved domain. We focused our research into
the materials characterization, materials at working
conditions and interaction of molecules with metal
surfaces. For material characterization, we applied
valence-to-core (v2c) RXES in order to probe, within the
same measurement, lowest unoccupied and highest
occupied electronic structure of different photo-catalytic
materials. Typical v2c-RXES plane for TiO2 anatase is
plotted in Figure 1 together with main electronic states
accessed by the experiment [5]. The measured spectra
can be compared with full-mutiple scattering calculations
for determination of main electronic states contributions
to the measured X-ray signals as demonstrated in
Figure 1. We showed that v2c-RXES measured with
dispersive-type spectrometer allow to probe very small
changes on electronic structure, which indeed have large
effects on catalytic properties of the material [6].
Electronic structure of matter probed under
in-situ conditions by means of X-ray
spectroscopy techniques
J. Szlachetko1,2*
1Paul
Scherrer Institute, SwissFEL, Switzerland
of Physics, Jan Kochanowski University, Kielce,
Poland
2Institute
Keywords: synchrotron radiation, in-situ X-ray spectroscopy,
resonant X-ray emission, X-ray free-electron laser
*e-mail: [email protected]
The study of chemical processes at in situ conditions
is a challenging task due to the often extreme reaction
conditions, reaction complexity, reaction time scales and
low chemical sensitivity to the element of interest. The
available techniques are usually too slow or insensitive to
probe reaction intermediates. X-rays based techniques
are an ideal tool for the in-situ study because of their
penetration properties, chemical specificity and
sensitivity. The X-ray absorption and emission
spectroscopy (XAS/XES) or their combination, resonant
emission X-ray spectroscopy (RXES), allows for
accurate mapping of local electronic and geometric
structures in catalytic and biologically relevant systems
[1].
I will present recent advances in in-situ RXES
techniques, with main focus on application to chemistry
and material science. I will also discuss, improvements in
chemical sensitivity as well as temporal resolution by
means of high energy resolution off-resonant
spectroscopy (HEROS) technique [2]. Fixed optical
arrangement of HEROS methodology allowed us for subsecond measurements at synchrotron [2] and shot-to-shot
spectroscopy at XFEL [3]. Finally I will discuss recent
experiments at XFEL where self-amplified spontaneous
emission operation of LCLS machine was employed for
RXES spectroscopy on 3d metal-complexes to probe the
non-linear regimes of X-ray interaction with matter.
Figure 2. (a) Schematic representation of the RXES process in
a Au atom. (b) Experimental setup for time-resolved RXES.
The Au2O3 powder is enclosed in a reactor cell and heated up in
a reducing H2 environment. (c) Time evolution of the RXES
spectra during the experiment (time-resolved RXES) and
schematics of the data analysis procedure employing genetic
algorithm computations. From [7].
In order to apply RXES technique for in-situ time
resolved studies and to probe materials under working
conditions, the core-to-core (c2c) transitions are used that
allow for more efficient detection in combination with
dispersive spectrometer for quick spectral acquisition [7].
The typical in-situ experimental scheme is drawn in
Figure 1. (Left) TiO2 anatase RXES plane. (top) Non-resonant
XES spectrum; (right) TFY- XAS versus HR-XAS extracted at
constant emission energy (4931.7 eV). Right) Valence and
conduction band electronic states extracted from measured
RXES plane (top); calculated Ti, O, and N DOS for TiO2 and
TiN (below). From [5].
1
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Figure 2b, used for study temperature-programmed
reduction of Au2O3. From the experiment a short-lived
Au2O compound has been detected for the first time
under in situ conditions. On the basis of time-resolved
RXES data analysis combined with genetic algorithm
methodology (Figure 2c), we could determined the
electronic structure of the metastable Au2O intermediate
species. The result was confirmed with support of DFT
calculations and we found that such a structure may
indeed be formed and that the expanded lattice constant
is due to the termination of Au2O on the Au2O3 structure.
The in-situ c2c RXES also proofed to be ideal tool to
probe electronic structure changes of surface metals
interacting with molecules. We showed, that based on
electronic structure changes detected by RXES with
support of theoretical calculations, and it is possible to
determine not only the metal density of states, but also
the geometry at which a molecule bounds to the metal
structure [8]. Finally, I will describe on how the high
chemical sensitivity c2c-RXES allow to track at in-situ
conditions interaction of Pt-based drugs with DNA
structure [9]. Further prospects on technical
developments for simultaneous c2c and v2c RXES
spectroscopy will be described as applied to anti-cancer
drug studies and binding mechanisms to DNA.
needed to promote the core-electron above the Fermi
level. Most importantly, in the off-resonant excitation
regime, the shape of the X-ray emission spectrum is
dominated by the shape of the unoccupied density of
states; i.e. proportional to X-ray absorption spectrum
[10]. By combination of off-resonant excitation regime
and high energy resolution dispersive-type detection,
HEROS methodology was applied to monitoring the
kinetics of chemical reactions [11]. Thanks to applied
scanning-free approach, tracking of chemical reactions in
gas-switching
or
temperature
programed
reduction/oxidation experiments at sub-second time
resolution was possible and allowed to determine
intermediate species involved in reactions. Recently we
demonstrated that HEROS approach is free of selfabsorption effects which very often affects the spectra
measured by fluorescence X-ray absorption [12].
The fixed optical geometry of the von Hamos
spectrometer has allowed us to probe the unoccupied
electronic states of a solid sample using HEROS on a
shot-to-shot basis at an XFEL source. The experiment
was performed at the CXI experiment station at the Linac
Coherent Light Source, USA, and was focused on
studying the X-ray interaction with solid matter under
off-resonant conditions [3].
In Figure 3 we plot experimental XFEL data for Cu
metal at an incidence X-ray energy tuned to -12eV below
the K-shell X-ray absorption edge. The measured
HEROS spectrum is compared to the result of theoretical
calculations employing Kramers-Heisenberg relation
[10]. In the calculations we used an X-ray absorption
spectrum measured at a synchrotron facility. As shown in
figure 3, a good agreement is obtained indicating that the
same electronic states are probed with HEROS at an
XFEL and X-ray absorption at a synchrotron source.
Finally, I will present the preliminary results from XFEL
experiments where the nonlinear two-photon absorption
(TPA) process in condensed matter was observed. In
application at hard X-ray energies, the TPA in condensed
matter was observed for the first time only recently [13].
Comparing to one photon absorption which is determined
by dipole-allowed transitions, the TPA process requests
changing the electron quantum number by +/-2 or 0,
allowing thus to access a quadrupole or forbidden
excitations. Therefore, the TPA process may allow, for
example, to study quadrupole-allowed transitions in
K-edge spectroscopy in 3d- or 4d-type metal compounds.
However, at this point, a number of fundamental
experiments have to be performed first before a real
approach to applied TPA spectroscopy.
Figure 3. HEROS spectra of Cu recorded for 2000 self-seeded
pulses at LCLS (black curve). For comparison, we plot the
calculated spectrum using the Kramers-Heisenberg relation
with a Cu K-edge X-ray absorption spectrum as input for
calculations.
In the second part of the presentation I will focus
on development of high energy resolution off-resonant
spectroscopy (HEROS) in application to time-resolved
in-situ spectroscopy and shot-to-shot spectroscopy at
XFELs. The off-resonant excitation relates to the secondorder photon-atom interaction, in which the energy of the
incidence X-ray is smaller than the binding energy of
core-electron. Nonetheless, due to the photon-electron
interaction, a core electron may be excited into an
unoccupied state above the Fermi level. This
intermediate ‘‘virtual’’ state of the neutral atom decays
then radiatively, with the initial core hole being filled by
another inner-shell electron. Because the total energy of
this scattering process has to be preserved, the energy of
the emitted X-ray is lower by the amount of energy
___________________________________________________
[1] J. Szlachetko, Y. Kayser, Techniques: RXES, HR-XAS,
HEROS, GIXRF, and GEXRF, (CRC Press, Taylor &
Francis Group, New York, 2014).
[2] J. Szlachetko et al., Chem. Comm. 48 (2012) 10898..
[3] J. Szlachetko et al., Struct. Dyn. 1 (2014) 021101,
M. Kavcic et al., Phys. Rev. B 87 (2013) 075106.
[4] J. Szlachetko et al., Rev. Sci. Instr. 83 (2012) 103105.
[5] J. Szlachetko, J. Sa, CrystEngComm 15,(2013) 2583.
[6] J. Szlachetko et al., J. Chem. Sci. 126, (2014) 511,
K. Kollbek et al., Rad. Phys. Chem. 93 (2013) 40,
2
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
K. Kollbek et al., Appl. Surf. Sci. 281 (2013) 100,
J. Szlachetko et al., RSC Advances 4 (2014) 11420, K.
Zakrzewska et al., Int. J. Hydrogen Energ. 40 (2015) 815.
[7] J. Szlachetko et al., J. Phys. Chem. Lett. 5 (2014) 80,
J. Sa et al., Phys. Chem. Chem. Phys., 16 (2014) 7692,
J. Szlachetko et al., J. El. Spectr. Rel. Phenom. 188,
(2013) 161.
[8] J. Sá et al., Nanoscale, 5, 8462 (2013),
J. Sá et al., RSC Adv., 3, (2013) 12043,
C. Lothschütz et al., ChemCatChem 6 (2014) 443,
M. Zienkiewicz et al., Dalton Trans. 43 (2014) 8599,
M. Zienkiewicz et al., Dalton Trans., 42 (2013) 7761,
H. G. Manyar et al., Catal. Sci. Technol., 3, (2013) 1497,
J. Václavík et al., ChemCatChem Comm. 5, (2013) 692,
O. Safonova et al., Phys. Chem. C 118 (2014) 1974,
R. Kopelent et al., Angew. Chem. Int. Ed. 54 (2015) 1.
[9] E.Lipiec et al., Dalton Trans. 43 (2014) 13839,
G. Berger et al., J. Biol. Inorg. Chem. (2015)
doi:10.1007/s00775-015-1270-6.
[10] J. Tulkki, T Aberg, J. Phys. B: At. Mol. Phys. 15 (1982)
L435,
J. Tulkki, Phys. Rev. A 27 (1983) 3375,
H. Hayashi et al., Chem. Phys. Lett. 371 (2003) 125,
H. Hayashi et al., Phys. Rev. B 68 (2003) 045122,
J. Szlachetko et al., Phys. Rev. Lett. 97 (2006) 073001.
[11] J. Szlachetko et al., J. Am. Chem. Soc. 135 (2013) 19071,
C. Milne et al. Coord. Chem. Rev. 277 (2014) 44,
J. Sa, Recycl. Catal. 2 (2015) 23.
[12] W. Błachucki et al., Phys. Rev. Lett. 112 (2014) 173003.
[13] K. Tamasaku et al., Nature Photon. 8 (2014) 31.
3
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-02
Figure 3 illustrates example of a significant difference of quality of chemical analysis. A partially charged
electrode of LiFePO4 battery [2] was analyzed using the
beamline 11.0.2 STXM in real space mode and calculated spatial resolution was about 70 nm while analysis of
ptychographic measurements yielded component mapping with about 6 nm resolution.
Tue. 01. 09., 1020-1100
Soft X-ray Absorption Spectroscopy – Chemical
Analysis on nanoscale
T. Tyliszczak*
Advanced Light Source, Lawrence Berkeley National
Laboratory, Berkeley, CA 94720, USA
Keywords: synchrotron radiation, X-ray spectromicroscopy
*e-mail: [email protected]
The soft X-ray scanning microscopes are used
primary for utilization of X-ray absorption spectroscopy
on nanoscale. Typically, the spatial resolution is being
quoted using resolution of individual images. Presently,
those images can be recorded with 15-25 nm resolution.
Unfortunately, spatial resolution for spectroscopic
analysis can be much worse. The reason for this
reduction of resolution is a shape of the zone plate
focused X-ray beam (Figure 1). Almost all soft X-ray
microscopes are using zone plates as focusing elements
thus most of the spectroscopic analysis can have limited
resolution.
Figure 3. Maps of lithiated and delithiated components of
partially charged FeLiPO4 electrode from a stack of images
recorded around Fe L3 absorption edge using real space
imaging with 25 nm zone plate (top) and ptychography with 60
nm zone plate (bottom).
Figure 1. Typical focused beam profile. Up to 50% intensity
can be in the beam wings.
Recent development of ptychography (Difraction
Enchenced Scanning Transmission Microscopy) [1] can
overcome the limitation in spatial resolution for
spectroscopy because the beam shape is deconvoluted in
the final reconstruction of images. While soft X-ray
ptychography can be used for imaging with exceptional
resolution of 2 nm, the application for the spectroscopic
analysis is even more important because it favorable can
compete with TEM/EELS analysis.
Acknowledgments: This work was performed at the ALS. The
Advanced Light Source is supported by the Director, Office of
Science, Office of Basic Energy Sciences, of the U.S.
Department of Energy under Contract
No. DE-AC02-05CH11231.
___________________________________________________
[1] D. A. Shapiro, Y.-S. Yu, T. Tyliszczak, J. Cabana,
R. Celestre, W. Chao, K. Kaznatcheev,
A. L. D. Kilcoyne, F. Maia, S. Marchesini, S. Meng,
T. Warwick, L. L. Yang, H. A. Padmore,
Nature Photonics 8 (2014) 765.
[2] W. C. Chueh, F. El Gabaly, J. D. Sugar, N. C. Bartelt,
A. H. McDaniel, K. R. Fenton, K. R. Zavadil,
T. Tyliszczak, W. Lai, K. F. McCarty,
Nano Letters 13 (2013) 866.
Figure 2. Test pattern image at 1500 eV.
4
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-03
Extended abstract
3300 nm. It was shown that the films in the composition
range of 0.17<x<0.75 are amorphous while those outside
this range are crystalline (either single crystalline or
polycrystalline).
The composition dependence of the optical band gap
energy for both crystalline and amorphous GaN1−xAsx
alloys were compared directly with calculated
composition dependence of the band gap. It was shown
that the band gap values for the amorphous GaN1−xAsx
alloys cannot be explained by the virtual crystal
approximation (VCA) or the fitted curve using a single
bowing parameter of 16.2 eV. Simultaneously, excellent
agreement can be observed between the band gap values
for the crystalline alloys and the band anticrossing
(BAC) model [1-2]. The deviation of the experimental
optical absorption results from the BAC calculations
found for the amorphous alloys is not unexpected as the
model has been developed for crystalline materials.
Additional uncertainty is introduced by the fact that the
band gap has been calculated as a composition weighted
interpolation of the BAC model results and is less
accurate for the alloys in the middle range of
compositions.
Tue. 01. 09., 1420-1500
Elemental and orbital-selective characterization
of semiconductor materials by X-ray
spectroscopy - XAS, RIXS and XPS
I. N. Demchenko*
Institute of Physics PAS, al. Lotnikow 32/46, 02-668 Warsaw,
Poland
Keywords: synchrotron radiation, XAS, XES, RIXS, XPS
*e-mail: [email protected]
The ability to control the physical properties of novel
materials, by controlling crystallographic structure,
arrangement of atoms inside sample's volume and along
the surface taking into account point defects, is of crucial
importance nowadays from both fundamental and
applied research points of view. As electronic structure
ultimately determines physical properties of matter, it is
natural to anticipate that knowledge of it for existing
systems together with the ability to describe and predict
it for new systems will bring progress in science and
technology to a new level. Among the ways to reach such
information X-ray spectroscopy techniques stand
considerably out due to their capabilities to provide
detailed information on material electronic structure and
thus helping us to construct the informational bridge
between the structural and electronic properties of wide
class of materials.
This communication focuses on just a few (out of
plenty) techniques, namely X-ray absorption/emission
spectroscopy, Resonant inelastic X-ray scattering, and Xray photoelectron spectroscopy and their application to
characterize semiconductor materials is presented with
examples.
1. Application of X-ray spectroscopy to highly disordered
systems.
Opposite to the very extensively studied As-rich
GaNAs alloys much less work has been devoted to
highly mismatched alloys (HMAs) on the N-rich side of
this alloy system. In these studies a highly mismatched
GaN1−xAsx alloy system was successfully synthesized in
the whole composition range using a nonequilibrium low
temperature molecular beam epitaxy technique [1]. In
addition to other techniques X-ray spectroscopy was
utilized to determine the reorganization of electronic
(around Fermi level) and atomic structure of novel
GaN1−xAsx system in the whole composition range.
Examination of atomic structure by X-ray diffraction for
the most part of samples was impossible since obtained
films had no long ordering, i.e. had amorphous structure.
It is an important fact that crystallinity is not required for
X-ray spectroscopy measurements, making it one among
a few structural probing techniques available for
noncrystalline and highly disordered materials, including
solutions.
The optical gaps of the GaN1−xAsx alloys were
measured by absorption using a LAMBDA-950
UV/vis/NIR spectrophotometer over the range of 190–
Figure 1. Composition dependence of the CBM and the VBM
energies for GaN1−xAsx alloys as measured by XAS and SXE,
respectively, plotted together with the BAC predicted values.
The linear interpolations of CB and VB between end point
compounds (GaN and GaAs) are also shown. The positions of
the H2O2 redox potentials with respect to the VBM of GaN
are also shown.
According to the BAC model the observed reduction
in the band gap can be attributed to an upward shift of
the valence band edge (VBE) and a downward
movement for the conduction band edge (CBE) in the
N-rich and As-rich GaN1−xAsx alloys, respectively.
However, the absolute movement of the conduction band
(CB) and valence band (VB) of the GaN1−xAsx alloys
cannot be derived from conducted optical measurements.
To examine electronic structure of investigated system
around Fermi level the combination of soft X-ray
emission (SXE) and X-ray absorption (XAS)
spectroscopies with the following interpretation of
obtained results were done. XAS and SXE directly probe
the partial density of states (DOS) of the CB and VB,
respectively [1]. Overlapping the SXE and XAS spectra
5
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
with reference to the core level provides a direct
measurement of the energy positions of the VB and CB
states in semiconductor materials. For this purpose, the
nitrogen K-edge (around 400 eV) was investigated at
room temperature at the Advanced Light Source (ALS)
on beam line 8.0.1. XAS was detected by the total
fluorescence yield detection mode with an energy
resolution of about 0.2 eV, and SXE was measured using
the Tennessee/Tulane grating spectrometer with a total
energy resolution of 0.6 eV.
The absolute positions of the CBE and VBE are
directly measured as a function of composition and
compared to the results of conventional optical
measurements [1]. The composition dependence of the
CBE and the VBE energies at N sites of GaN1−xAsx alloy
as measured by XAS and SXE were displayed together
with the BAC predicted values (see Fig. 1). It should be
pointed out here that the calculated band movements by
an interpolation of the BAC model are included for
comparison purposes only. Band movements in the
amorphous alloys may vary dramatically from those of
crystalline alloys. Both CBE and VBE are observed to
shift as x increases. A jump in the VBE to higher energy
for dilute As (x ~ 0.10) polycrystalline samples as
compared to GaN is observed consistently with the BAC
model. A second jump to lower energy is observed in the
CBE upon entering into the amorphous phase (x ~ 0.17).
For increasing x in the amorphous phase, both the VBE
and CBE are only very weakly shifting to higher and
lower energies, respectively. Finally a smaller jump in
the VBE yet again to a higher energy is observed for the
amorphous to As-rich polycrystalline transition (x~0.70).
Not unexpectedly the smooth interpolation of the BAC
model from the dilute polycrystalline regions does not
explain the discontinuous energy jumps into the
amorphous phase. It should be also pointed out that the
band gap energies measured by XAS and SXE are lower
than the values obtained by optical absorption. This may
be attributed to excitonic coupling between the screened
core hole and conduction electron.
In order to probe the bulk-sensitive occupied valence
band electronic structure, near-threshold excitation X-ray
emission spectra were recorded for CdO films for
excitation energies at the O K absorption threshold [4].
Main idea of this research was to demonstrate that the
XES experiments are unique since they can provide
direct evidence to the band structure of a semiconductor,
in particular whether a semiconductor has direct or
indirect band gap, without further theoretical input.
2. Potential of combined soft X-ray emission and
absorption spectroscopies for estimation of direct and
indirect bandgaps size in semiconductors.
With the arrival of high-brilliance third-generation
synchrotron sources, a new approach to study the bulk
band structure has been established, namely to utilize
resonant inelastic X-ray scattering (RIXS). In RIXS, an
electronic Raman scattering process is used to select
specific excitations of valence electrons into unoccupied
conduction band states. In other words, a core electron is
resonantly excited into an unoccupied state at a certain k
value, and the resonant fluorescence decay of a valence
electron with the same k value into the core hole is
detected. The observed RIXS spectrum thus contains
momentum-resolved information about the occupied and
unoccupied electronic states, which can be analyzed
based on the Kramers-Heisenberg formalism [3]. Since
the reachable information depth is typically of the order
of a few hundred nanometers, study of systems with
poorly defined surface properties or protective cap layers
becomes possible.
Figure 2. (a) Intensity maps of normalized RIXS and partially
coherent fractions of XES corresponding to (b) standard and
(c) intermediate approaches. Intermediate procedure works
well for visualization of branching dispersion of occupied
states. The details will be discussed during the presentation.
In a XES experiment the band-gap type can be
determined by observing the emission spectra as a
function of excitation energy. In case of a direct energy
gap material, emission at the highest energy is expected
for an excitation energy in the vicinity of the absorption
threshold (into the conductive band minimum, CBM). As
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
the excitation energy increases the emission should shift
to a lower energy. For indirect band-gap materials the
opposite behavior is expected, i.e., a shift of the emission
spectrum (namely, top of the valence band maximum,
VBM) to higher energy with increasing excitation
energy. In another words, as the excitation energy
increases, the probing transitions get closer, in k space, to
the top of the VB. Our XES/RIXS data, see Fig. 2 and
[4], clearly show this tendency and will be discussed in
details.
Based on RSMS theory we were able to interpret the
experimental XAS spectra in terms of local geometrical
and electronic structures. Calculated near-edge structure
for cation and anion X-ray absorption edges represents a
good coincidence with experimental one. Calculated
PDOS describes well all features corresponding to
unoccupied states of investigated films and allows to
conclude that the orbital character of the lowest energy of
the CB is mostly Cd 5s-O 2p σ*. Presented RIXS CdO
data set is showing a progressively varying partial k
mixing of initial and final states near the threshold and
thus a varying incoherent line shape. Overlapping of
XAS spectrum with RIXS ones makes possible to
estimate both direct ~2.4 eV and indirect ~0.9 eV
bandgap values. The obtained results are consistent with
the theoretical/experimental ones presented in the
literature and our own optical absorption results.
Si/Nb/Si structures. By repeated ion etching and XPS
measurements (i.e. depth profiling), the depth
distribution of the elements in the investigated samples
were determined (see, for example, Fig. 3). The obtained
results for Nb layers with different thickness buried in Si
matrix will be shown and discussed in details.
100
a-Si/9.5nm Nb/a-Si/glass
(a)
80
60
AC [%]
O 1s
Si 2p
Nb 3d
40
20
0
0
10
20
30
40
50
60
70
Sputter time (min)
Nb 3d
50
(b)
-70.00
1330
2730
4130
5530
6930
8330
9730
1.113E+04
1.253E+04
1.393E+04
1.533E+04
1.673E+04
1.813E+04
1.953E+04
2.093E+04
2.233E+04
2.373E+04
45
3. The properties of ultrathin superconducting films by
X-ray photoelectron spectroscopy.
One of the fundamental problems in nanoscience
research is a question about the nature of the ground state
in confined systems, particularly in the case of the
superconducting (SC) materials. It is well established
that the reduction of the thickness of SC films leads to
the superconductor-insulator transition (SIT) [5-6]. The
usual assumption is that the SIT is induced by disorder
which reduces mean-free path. In [7] authors
demonstrate an example of the SIT for which its origin
may be even more complex. The structural and
magnetotransport properties in a series of Si/Nb/Si
trilayers grown by magnetron sputtering at room
temperature are shown. The thickness of Nb, d, is varied
from 20 nm down to 1.1 nm with a fixed Si thickness of
10 nm. The high-resolution TEM and the X-ray
diffraction indicate that for d > 6 nm the films are
polycrystalline, while they become amorphous for
smaller d. The Hall effect measurements reveal that the
positive Hall coefficient, characteristic for bulk Nb, starts
to decrease for d below 6 nm, and eventually changes
sign into negative for d below 2 nm. The slight
nonlinearity of the Hall voltage versus magnetic field is
observed in the thinnest samples (d about 1.3 nm), which
may indicate the presence of two types of carriers. The
possible origins of this effect may include the
modification of the niobium band structure or the
contribution of the Nb-Si interface to the conduction.
Therefore, surface analysis studies by X-ray
photoemission spectroscopy were conducted to
investigate the electronic structure, the valence band,
core levels of related components, and the relative
positions of the energy levels involved in the interface of
Sputter time (min)
40
35
30
25
20
15
10
5
201
202
203
204
205
206
207
208
209
210
Binding Energy (eV)
Figure 3. (a) Concentration–depth profile of the
a-Si/9.5 nm Nb/a-Si trilayer at glass substrate. (b) Contour plot
of Nb 3 d spectra during a depth profiling experiment.
Acknowledgments: The author wishes to thank W. Lisowski
(IPCh PAS) for experimental support and useful discussions.
___________________________________________________
[1] K. M. Yu, S. V. Novikov, R. Broesler, I. N. Demchenko
et al, J. Appl. Phys. 106 (2009) 103709.
[2] W. Shan, W. Walukiewicz, J. W. Ager III, E. E. Haller et
al, Phys. Rev. Lett. 82 (1999) 1221.
[3] M. Rovezzi, P. Glatzel, Semicond. Sci. Technol. 29
(2014) 023002.
[4] I. N. Demchenko, J. Denlinger, M. Chernyshova, K. M.
Yu et al, Phys. Rev. B 82 (2010) 075107.
[5] C. A. Marrache-Kikuchi, H. Aubin, A. Pourret, K. Behnia
et al, Phys. Rev. B 78 (2008) 144520.
[6] T. I. Baturina, C. Strunk, M. R. Baklanov, A. Satta, Phys.
Rev. Lett. 98 (2007) 127003.
[7] I. Zaytseva, O. Abal’oshev, P. Dluzewski,W. Paszkowicz,
L. Y. Zhu, C .L. Chien, M. Konczykowski,
M. Z. Cieplak, Phys. Rev. B 90 (2014) 060505(R).
7
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-04
scattering vector Q = 4πsinθ/λ = 23 Å-1, where 2θ is the
scattering angle and λ is the wavelength.
As the atomic scale structure of the investigated
materials cannot be described using formalism of
crystallography an approach based on the Reverse Monte
Carlo [1] fitting procedure was used. In this method
Marcov chain sampling with the Metropolis accelerating
algorithm [2] allows generation of three dimensional
particle configuration that is consistent with the
experimentally measured structure factor. The fit quality
is evaluated by a standard χ2 test in which the
experimental errors are taken into account.
In our previous paper [3] the local atomic
arrangement in the Fe80B20 glass was compared with
those of the Fe3B, Fe23B6 and bcc Fe crystalline phases.
From this comparison it has been concluded that the local
structure of the crystalline counterparts is not consistent
with the experimental data for glassy Fe80B20.
The Reverse Monte Carlo method applied for the
Fe80B20, Co80B20 and Mg60Cu30Y10 metallic glasses
allowed obtaining
perfect fit to the experimental
structure factors and to the experimental pair distribution
functions. Resemblance of the local structure, which
extends up to approximately 20 Å, to the icosahedral and
trigonal prism configurations is discussed. The Reverse
Monte Carlo results are compared with high-resolution
transmission electron microscopy observations. From
this comparison it can be concluded that both methods
lead to consistent description of the local atomic
arrangement in the investigated materials.
Tue. 01. 09., 1500-1540
Wide-angle X-ray scattering and Reverse Monte
Carlo studies of Fe80B20, Co80B20, Mg60Cu30Y10
metallic glasses
A. Burian1,2*, R. Babilas3, A. Fitch4, L. Temleitner5
1A.
Chełkowski Institute of Physics, University of Silesia, ul.
Uniwersutecka 4, 40-007 Katowice, Poland
2Silesian Center of Education and Interdisciplinary Research,
ul. 75 Pułku Piechoty, 40-500 Chorzów, Poland
3Institute of Engineering Materials and Biomaterials, Silesian
University of Technology, ul. Konarskiego 18a, 44-100
Gliwice, Poalnd
4European Synchrotron Radiation Facility, B.P.220, F-38043
Grenoble Cedex, France
5 Institute for Solid State Physics and Optics, Wigner Research
Centre for Physics, Hungarian Academy of Sciences, PO Box
49, H-1525 Budapest, Hungary
Keywords: synchrotron radiation, metallic glasses, wide-angle
X-ray scattering, Reverse Monte Carlo
*e-mail: [email protected]
The atomic scale structure of Fe80B20, Co80B20 and
Mg60Cu30Y10 metallic glasses has been studied using the
wide-angle X-ray scattering and reverse Monte Carlo
methods. The Fe80B20 and Co80B20 samples were
prepared in the form of amorphous ribbons with
thickness of 0.03 mm and width of 5 mm by the “chillblock melt spinning technique under the argon protective
atmosphere. The bulk Mg60Cu30Y10 glass was obtained
by injection of the Mg-Cu-Y melted material in the
proportion 60:30:10 into a copper mold by a pressure
casting method.
The wide-angle X-ray scattering measurements were
performed on the ID31 beam-line at the European
Synchrotron Radiation Facility, Grenoble, France. The
incident beam energy of 31 keV yielding the wavelength
of 0.4 Å was used in this experiment. The scattered
intensities were recorded to the maximum value of the
Acknowledgments: This work was supported by the National
Science Centre under the research project No.:
2011/03/D/ST8/04138.
___________________________________________________
[1] R. L. McGreevy and L. Pusztai, Molecular Simulation
1 (1988) 359.
[2] N. Metropolis, A.W. Rosenbluth, M.N. Rosenbluth,
A.H. Teller, E. Teller, J. Chem. Phys. 21 (1953) 1087.
[3] R. Babilas, Ł. Hawełek, A. Burian, J. Solid State
Chemistry 219 (2014) 179.
[4] R. Babilas, R. Nowosielski, M. Pawlyta, A. Fitch,
A. Burian, Materials Characterization, in press.
8
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-05
transitions occurred in the end members of the systems.
In particular, SmCoO3 cobaltite undergoes magnetic,
spin-spin and metal-insulator transitions at 493 K, 605 K
and 693 K, respectively [2], whereas the SmFeO3 ferrite
shows spin-reorientation at 480 K and para- to
antiferromagnetic transition at 670 K [3]. Clear sign for a
magnetoelastic coupling has been detected in SmFeO3 at
the Néel-temperature of 675 K [4].
Wed. 02. 09., 0900-0940
Structural, electronic and magnetic phase
transitions in complex oxide perovskites probed
by X-ray synchrotron powder diffraction
L. Vasylechko1*, O. Pekinchak1, O. Pavlovska1,
R. Stepchuk1, Yu. Prots2, D. Chernyshov3
1Lviv
Polytechnic National University, 12 Bandera St., 79013
Lviv, Ukraine
2Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer
Str. 40, 01187 Dresden, Germany
3Swiss-Norwegian Beam Lines at ESRF, BP220, 38000, Grenoble,
France
Keywords: perovskites, phase transitions, synchrotron radiation
*e-mail: [email protected]
In situ temperature-dependence powder diffraction
examinations and analysis of thermal expansion is very
useful tool not only for the study of structural phase
transitions, but also for the investigation of diverse
electronic and magnetic phase transformations occurred
in complex oxide and intermetallic systems. Especially
this is important for the Pr- and Nd-based compositions,
where the spin-state transition is seen much better in the
thermal expansion data than in the magnetic
susceptibility due to the large contribution of the 4f
moments of Pr and Nd ions on the magnetic properties.
Our recent in situ X-ray synchrotron powder
diffraction investigations of the mixed cobaltites-ferrites
RCo1-FexO3 (R = Pr, Nd, Sm, Eu, Gd, Tb) performed at
ESRF beamlines BM1A and ID22 revealed anomalous
lattice expansion, which is reflected in a sigmoidal
dependence of the unit cell dimensions and in abnormal
anisotropic increase of the thermal expansion coefficients
(TEC) with (several) broad maxima in the temperature
range of 5001000 K, depending on the composition.
Thorough analysis of the selected bond lengths and
octahedra tilt angles, as well as the atomic displacement
parameters (adp’s) allows to detect extra structural
anomalies, which are evidently associated with the
electronic and magnetic phase transitions occurred in the
RCoO3RFeO3 systems at the elevated temperatures. As
an example, significant bond-length stretching inside
Co/FeO6 octahedra in SmCo0.7Fe0.3O3 structure at ~450 K
and at 720730 K (Fig. 1a) and corresponding extrema at
the adp’s curves (Fig. 1b) indicate the Jahn-Teller
distortion (which may be dynamic) associated with
excited spin states of Co3+ species. According to Ref. [1]
the transition from low-spin to intermediate/high-spin
state of Co3+ ions in RCoO3 series introduces bond length
fluctuation that suppresses the phonon contribution. It is
evident that observed structural anomalies in
SmCo0.7Fe0.3O3, like as in other RCo1-FexO3 perovskites
are associated with the magnetic and electronic phase
Figure 1. Temperature dependence of Co/Fe-O bond lengths (a)
and atomic displacement parameters (b) in SmCo0.7Fe0.3O3
structure reflecting a coupling of electronic and magnetic phase
transitions to the lattice
Acknowledgments: This work was supported in parts by the
Ukrainian Ministry of Education and Sciences (project
”KMON”) and ICDD Grant-in-aid program. High-resolution
X-ray synchrotron powder diffraction measurements were
carried out during beamtimes allocated to the ESRF
experiments CRG 01-02-1065 and MA-2320.
___________________________________________________
[1] J.-Q. Yan, J.-S. Zhou, J. B. Goodenough. Phys. Rev. B 69
(2004) 134409.
[2] K. Knizek, Z. Jirak, J. Hejtmanek, M. Veverka,
M. Marysko, G. Maris, T. T. M. Palstra. Eur. Phys. J. B
47 (2005) 213.
[3] J.-H. Lee, Y. K. Jeong, J. H. Park, M. -A. Oak, H. M.
Jang, J. Y. Son, J. F. Scott. Phys. Rev. Letters 107 (2011)
117201.
[4] C.-Y. Kuo, Y. Drees, M. T. Fernández-Díaz, L. Zhao,
L. Vasylechko, D. Sheptyakov, A. M .T. Bell, T. W. Pi,
H.-J. Lin, M.-K. Wu, E. Pellegrin, S. M. Valvidares,
Z.W. Li, P. Adler, A. Todorova, R. Küchler, A. Steppke,
L. H. Tjeng, Z. Hu, A. C. Komarek. Phys. Rev. Letters
113 (2014) 217203.
9
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-06
Extended abstract
symetrię kulistą, a ich promień rośnie liniowo z czasem.
Po wzajemnym zetknięciu się i utworzeniu granic
z sąsiadami, sferolity stają się wielościanami. Sąsiednie
lamele w sferolicie rozdziela faza amorficzna
zawierająca splątania, odgałęzienia i te fragmenty
łańcuchów, które nie wbudowały się w kryształ wskutek
odmiennej struktury chemicznej lub konfiguracji.
Polietylen (PE) krystalizuje głównie w dwóch
odmianach polimorficznych. Najbardziej rozpowszechnioną odmianą krystalograficzną PE jest odmiana
rombowa. Lamele krystaliczne tej odmiany utworzone są
z pofałdowanych makrocząsteczek (ang. folded-chain
crystals), przyjmujących konformację płaskiego zygzaka.
Pod wysokim ciśnieniem, powyżej 360 MPa, PE
krystalizuje w stabilnej fazie heksagonalnej [2].
Kryształy
tej
odmiany
utworzone
są
z rozprostowanych łańcuchów polimerowych (ang.
chain-extended crystals), co prowadzi do bardzo dużej
grubości krystalitów, porównywalnej do długości
całkowicie rozprostowanych makrocząsteczek. Faza
heksagonalna charakteryzuje się dużym stopniem
nieuporządkowania, jej gęstość jest o ok. 8,5 % mniejsza
od gęstości w pełni uporządkowanej odmiany rombowej.
Słabe oddziaływania w obrębie kryształu fazy
heksagonalnej umożliwiają dyfuzję makrocząsteczek
wzdłuż ich osi w obrębie kryształu (ang. sliding
diffusion) [3]. Na skutek tej dyfuzji kryształ odmiany
heksagonalnej
może
w sposób
nieograniczony
kontynuować wzrost w kierunku osi łańcuchów. Taki
mechanizm przyrostu grubości kryształu, traktowany
jako element pierwotnej krystalizacji, nazwano
„wzrostem przez pogrubianie” (ang. thickening growth),
w odróżnieniu od pogrubiania uformowanych już lamel
podczas wygrzewania (ang. lamellar thickening). Proces
formowania kryształów z rozprostowaniem łańcuchów
jest bardzo powolny i wymaga długich czasów
krystalizacji. Zmniejszenie ciśnienia i temperatury
prowadzi do transformacji fazy heksagonalnej do formy
rombowej.
Stabilność różnych odmian krystalograficznych
polimerów zależy nie tylko od parametrów
termodynamicznych takich jak ciśnienie i temperatura,
ale także od rozmiarów krystalitów. Przejawem tej
zależności jest dobrze doświadczalnie udokumentowany,
a teoretycznie opisany równaniem Gibbsa-Thomsona [4],
fakt zmniejszania się temperatury topnienia kryształów
lamelarnych wraz ze zmniejszaniem się ich grubości.
Zależność stabilności kryształów polimerowych od ich
rozmiarów jest różna dla różnych odmian polimorficznych. Stąd może się zdarzyć, że faza krystaliczna
o nieskończenie dużych rozmiarach, która przy danym
ciśnieniu i temperaturze jest niestabilna, dla rozmiarów
nanometrycznych staje się stabilna i polimer może
krystalizować w tej fazie pomimo, że warunki
termodynamiczne są poza reżimem jej stabilności. Dla
polietylenu oznacza to, że faza heksagonalna, która, jak
wspomniano powyżej, jest stabilna przy wysokich
ciśnieniach, może się tworzyć również pod ciśnieniem
atmosferycznym we wczesnych etapach procesu
krystalizacji, gdy rozmiary krystalitów są niewielkie.
W tych warunkach tworząca się faza heksagonalna jest
metastabilna i po osiągnięciu odpowiednio dużych
Wed. 02. 09., 0940-1020
Badanie w czasie rzeczywistym procesu
krystalizacji polietylenu przy zastosowaniu
rozpraszania promieniowania synchrotronowego
pod małymi kątami
Cz. Ślusarczyk
Zakład Fizyki i Badań Strukturalnych, Instytut Inżynierii
Tekstyliów i Materiałów Polimerowych, Akademia TechnicznoHumanistyczna, ul. Willowa 2, 43-309 Bielsko-Biała
Keywords: krystalizacja izotermiczna, polietylen, SAXS,
promieniowanie synchrotronowe
*e-mail: [email protected]
Krystalizacja jest jednym z najważniejszych
procesów kształtujących strukturę i własności materiałów
polimerowych. Proces ten, oprócz warunków
termodynamicznych
określonych
głównie
przez
temperaturę i ciśnienie, silnie zależy od mikrostruktury
makrocząsteczek
polimerowych.
Zasadniczym
warunkiem krystalizacji polimeru jest bowiem
regularność budowy makrocząsteczki łańcuchowej;
polimery izotaktyczne i syndiotaktyczne wykazują
zdolność do krystalizacji, podczas gdy ataktyczne nie
posiadają tej zdolności. Obecność rozgałęzień
w łańcuchu obniża z reguły zdolność polimeru
do krystalizacji.
Zgodnie z uznaną i szeroko stosowaną teorią
krystalizacji polimerów, opracowaną przez Lauritzena
i Hoffmana [1] i opartą na koncepcji wielokrotnego
fałdowania makrocząsteczek, proces krystalizacji jest
procesem dwuetapowym. W pierwszym etapie, zwanym
zarodkowaniem pierwotnym, w wyniku termicznych
fluktuacji gęstości lub obecności cząstek obcych
substancji
w stopionym
polimerze
tworzą
się
uporządkowane ugrupowania fragmentów makrocząsteczek, które stają się zarodkami dalszej
krystalizacji. W drugim etapie następuje wzrost
krystalitów, który odbywa się poprzez przyłączanie
segmentów makrocząsteczek do powierzchni bocznych
zarodków pierwotnych. Pojedyncze kryształy polimerów
mogą się tworzyć podczas krystalizacji z rozcieńczonych
roztworów, podczas gdy krystalizacja ze stężonych
roztworów i ze stanu stopionego zachodzi na ogół
w formie stosów kryształów lamelarnych, składających
się z równolegle ułożonych lamel krystalicznych
przedzielonych warstwami amorficznymi. Pojedyncza
lamela krystaliczna w takim stosie jest równoległościanem
o
wymiarach
poprzecznych
dużych
w porównaniu do grubości, która jest rzędu 10 – 30 nm.
Obszar amorficzny (interlamelarny) w stosie tworzą
pofałdowania łańcuchów, końce i pętle łańcuchów,
łańcuchy łączące lamele krystaliczne oraz krótkie
rozgałęzienia boczne. W jednorodnym polu temperatury
polimeru stosy lamel wzrastają z jednakową prędkością
we wszystkich kierunkach, co prowadzi do powstawania
agregatów kryształów lamelarnych, zwanych sferolitami.
Do momentu wzajemnego zetknięcia się sferolity mają
10
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
rozmiarów przechodzi w odmianę rombową. Po raz
pierwszy możliwość krystalizacji PE poprzez fazę
metastabilną została opisana w 1994 r. przez Kellera
i współpracowników [5], a doświadczalnie potwierdzona
dopiero w 2006 r. przez Tracza i współpracowników [6],
którzy, stosując mikroskopię AFM, zaobserwowali
tworzenie
się
fazy
heksagonalnej
dla
PE
krystalizowanego pod ciśnieniem atmosferycznym na
powierzchni grafitu pirolitycznego. Badania te miały
jednak charakter „statyczny”, tzn. polegały na obserwacji
kryształów fazy heksagonalnej uformowanych po
skrystalizowaniu w danych warunkach próbki polimeru.
W prezentowanej pracy przedstawiono wyniki badań
procesu krystalizacji izotermicznej polietylenu przy
pomocy
metody
małokątowego
rozpraszania
promieniowania rentgenowskiego (SAXS). Zastosowanie
promieniowania synchrotronowego pozwoliło zbadać ten
proces w warunkach dynamicznych i po raz pierwszy
zaobserwować w czasie rzeczywistym przebieg
krystalizacji PE poprzez metastabilną fazę heksagonalną.
W pracy badano przebieg krystalizacji izotermicznej
polietylenu wysokiej gęstości (HDPE) o średniej masie
cząsteczkowej
77000
g/mol
w
następujących
temperaturach [°C]: 40, 100, 110, 116, 118, 120, 122,
124. Synchrotronowe badania SAXS przeprowadzono
przy użyciu podwójnie ogniskowanej kamery X33
w laboratorium EMBL na pierścieniu akumulacyjnym
DORIS ośrodka badawczego HASYLAB-DESY
w Hamburgu. Proces krystalizacji prowadzono
w specjalnie skonstruowanej przystawce pomiarowej,
składającej się z dwóch piecyków grzejnych. W jednym
z nich próbka polimeru była topiona w temperaturze
200 oC, a następnie przy użyciu odpowiedniego
mechanizmu, bardzo szybko umieszczana w drugim
piecyku, w którym panowała dana temperatura
krystalizacji. Przystawka znajdowała się na linii
pomiarowej, co umożliwiło rejestrację krzywych
dyfrakcyjnych już po kilku sekundach od umieszczenia
próbki w danej temperaturze.
Analiza krzywych SAXS została przeprowadzona za
pomocą funkcji rozkładu odległości powierzchni
fazowych g1(r) (ang. IDF – interface distribution
function) [7], którą oblicza się, na podstawie
zarejestrowanego rozkładu natężenia rozpraszania I(s),
ze wzoru:
g1 (r )  16
(LC) i grubości warstwy amorficznej (LA). Rys. 1a
przedstawia ewolucję w czasie funkcji g1(r) dla próbki
krystalizowanej w temperaturze 122 °C, a Rys. 1b
przebieg zmian wielkości charakteryzujących strukturę
lamelarną, otrzymanych z funkcji g1(r).
1.40E-008
Lc
1.00E-008
8.00E-009
g1(r)
6.00E-009
4.00E-009
2.00E-009
0.00E+000
-2.00E-009
-4.00E-009
-6.00E-009
LP
-8.00E-009
0
100
200
300
400
500
600
700
800
r [A]
400
(b)
350
LP
LP, La, Lc [A]
300
Lc
250
200
150
100
La
50
0
1000
Log Time [s]
Rysunek 1. (a) Ewolucja funkcji rozkładu odległości
powierzchni fazowych g1(r) dla PE krystalizowanego
w temperaturze TC = 122 °C; (b) Przebieg zmian w czasie
krystalizacji w TC = 122 oC parametrów struktury
krystalicznej: wielkiego okresu LP, grubości lamel
krystalicznych LC, grubości warstwy amorficznej LA.
Zakres zmian grubości lamel krystalicznych zależy
silnie od temperatury krystalizacji, co przedstawia Rys.
2. Jak widać z tego rysunku, zależność LC od logarytmu
czasu krystalizacji jest liniowa, może zatem być opisana
równaniem LC = B1log(t) + B2, gdzie współczynnik B1
związany jest z szybkością przyrostu grubości lamel
krystalicznych w trakcie ich powstawania. Wartość
współczynnika B1, wyznaczona metodą regresji
liniowej, zależy od temperatury krystalizacji TC
(Rys. 3). Dla przykładu B1 = 71,1 ± 1,1 w temperaturze
TC = 122 °C, podczas gdy dla TC = 116 °C wartość B1 =
11,7 ± 1,7. Tak duża różnica w szybkości przyrostu
grubości lamel krystalicznych wskazuje na odmienny
mechanizm krystalizacji PE w tych temperaturach.
Ponieważ duża szybkość zmian grubości lamel
krystalicznych wymaga dużej mobilności łańcuchów
polimerowych, takiej jaką mają makrocząsteczki PE w
fazie heksagonalnej, to wynika stąd , że w temperaturze
TC = 122 °C polimer ten krystalizuje właśnie w tej fazie
poprzez mechanizm wzrostu przez pogrubianie
(thickening growth). W temperaturze TC = 116 °C
natomiast nie obserwuje się tworzenia metastabilnej

3
(a)
La
1.20E-008
 G (s) cos(2rs)ds
1
0
w którym funkcja G1(s) nosi nazwę funkcji
interferencyjnej układu lamelarnego (ang. interference
function) i jest obliczana ze wzoru:
G1 (s)  lim I (s)s 4  I (s)s 4
s 
W powyższych zależnościach s = 2sinθ/λ jest wartością
wektora rozpraszania; λ jest długością fali
promieniowania rentgenowskiego, zaś 2θ jest kątem
rozpraszania. Dla rzeczywistego układu lamelarnego
funkcja g1(r) posiada ekstrema, z położeń których
bezpośrednio otrzymuje się wartości wielkiego okresu
struktury lamelarnej (LP), grubości lamel krystalicznych
11
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
fazy heksagonalnej; PE krystalizuje bezpośrednio
w stabilnej w tych warunkach odmianie rombowej,
a obserwowany przyrost grubości lamel związany jest
z typowym, często obserwowanym procesem ich
pogrubiania (lamellar thickening). Tak więc możliwy
jest, przewidziany przez Kellera, przebieg procesu
krystalizacji polietylenu w warunkach ciśnienia
atmosferycznego, w którym faza heksagonalna tworzy
się wcześniej niż stabilna w tych warunkach faza
rombowa tego polimeru.
80
70
60
B1
50
40
30
20
10
320
100
104
108
112
116
120
124
o
TC [ C]
300
Crystal thickness Lc [A]
280
260
Rysunek 3. Zależność współczynnika B1 od temperatury
krystalizacji izotermicznej TC.
240
220
200
o
180
TC= 40 C
160
TC= 116 C
___________________________________________________
o
o
[1] J. D. Hoffman, G. T. Davis, J. I. Lauritzen, Treatise on
Solid State Chemistry (red. N.B.Hannay, vol.3, Plenum
Press, New York 1976).
[2] G. C. Bassett, Polymer 17 (1976) 460.
[3] M. Hikosaka, S. Rastogi, A. Keller, H. Kawabata,
J. Macromol. Sci. Phys. B31 (1992) 87.
[4] P. J. Flory, A. Vrij A, J. Am. Chem. Soc. 85 (1963) 3548.
[5] A. Keller, M. Hikosaka, S. Rastogi, A. Toda, P. Barham,
P. G. Goldbeck-Wood, J. Mater. Sci. 29 (1994) 2579.
[6] A. Tracz, I. Kucinska, J.K. Jeszka, Polymer 47 (2006)
7251.
[7] J. W. Ruland, Coll. Polym. Sci. 255 (1977) 417.
[8] S. V. Krivovichev, Angew. Chem. 53 (2014) 654.
TC= 118 C
140
o
TC= 120 C
120
o
TC= 122 C
100
80
10
100
1000
Log Time [s]
Rysunek 2. Zależność grubości lamel krystalicznych LC od
logarytmu czasu krystalizacji dla różnych temperatur
krystalizacji izotermicznej.
12
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-07
spectroscopies. More detailed information about the
coordination sphere of bioactive complexes is obtained
by applying the X-ray absorption spectroscopy. Extended
X-ray absorption fine structure (EXAFS) analysis
provides information about the average coordination
number, the type of atoms around the metal ion and the
distances between the metal center and the coordinating
molecules. This data allows proposing a coordination
mode of ligands to the metal cation in the studied
complexes. From XANES spectra (X-ray absorption near
edge structure) it is possible to determine the oxidation
state of the metal in the analyzed compounds. In
addition, by taking advantage of the fact that the shape of
XANES spectra strongly depend on the angles between
central and neighboring atoms, the analysis of these
spectra allow confirmation and improvement of the
coordination modes proposed from the EXAFS analysis.
Moreover, the density functional theory level
calculations are carried out. The theoretical study on
metal complexes (geometry optimization, calculations of
vibrational frequencies, simulations of UV-Vis spectra
etc.) complements the experimental data.
During presentation the structural studies on
complexes with derivatives of coumarin (O-donor
ligands) and derivatives of thiourea (N,S-donor ligands)
will be presented.
Wed. 02. 09., 1420-1500
Structural studies of metal-organic ligand
complexes using X-ray absorption spectroscopy
A. Drzewiecka-Antonik1*, M. T. Klepka1, A. Wolska1,
P. Rejmak1
1Institute
of Physics PAS, Warsaw, Al. Lotnikow 32/46, PL02668 Warsaw, Poland
Keywords: XAFS, metal-organic ligand complexes
*e-mail: a[email protected]
The discovery that the metal complexes, especially
with transition metals like copper and silver, can be more
effective than the parent ligands opened a new field of
drug research. In our laboratory the synthesis and
structural characterization of novel biologically active
metal-organic ligand complexes is carried out.
The direct, hydrothermal and electrochemical
synthesis are used for complexation reactions. New
compounds (copper and silver complexes) are tested for
microbiological activity on standard and clinical strains
of fungi and bacteria. The use of the microorganisms
taken from patients is an important stage of our studies.
As a result of the civilization development and the
various human activities (e.g. inappropriate use of
antibiotics) the mutation of infecting cells of bacteria and
fungi is observed. We want to face this problem and
obtain metal-based complexes with high selectivity and
efficacy.
The
synthesized
compounds
are
initially
characterized by elemental analysis, IR and UV-VIS
Acknowledgments: Experimental research was funded from
the Polish National Science Centre(Grant No. UMO2012/07/D/ST5/02251). This work was supported in part by
PL-Grid Infrastructure. P. Rejmak acknowledges EAgLE
project no. 316014 for the financial support.
___________________________________________________
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-08
frequency vs. temperature was observed for ZnTe-like
and HgTe-like TO-phonon modes [5]. Since these
dependencies are resonant, the phenomenon explanation
is based on the modified Kawamura model [6].
Wed. 02. 09., 1500-1540
Study of phonon spectra of (Cd,Hg)Te-based
semiconductor solid solutions using synchrotron
radiation
J. Cebulski1*, E Sheregii1, J. Polit1 , A. Kisiel2,
A. Marcelli3, B. V. Robouch3, M. Piccinini 3
1Chair
of Applied Physics, University of Rzeszow, Pigonia 1,
35–310 Rzeszow, Poland
2Instytut Fizyki, Universytet Jagiellonski, Reymonta 4, 30-059
Krakow, Poland
3Istituto Nazionaledi Fisica Nucleare – Laboratori Nazionalidi
Frascati,Via E.Fermi 40,00044 Frascati, Italy
Keywords: synchrotron radiation, phonon spectra
*e-mail: [email protected]
Let me present an overview of recent achievements
made by the Polish-Italian team in our more than 15-year
collaborative
research
on
(Cd,Hg)Te-based
semiconductor solid solutions. The specialized source of
synchrotron radiation available in DAȹNE-light
laboratory at Frascati (Italy) [1] was used for far-infrared
reflection measurements FTIR. Optical TO-phonon
spectra were interpreted within the framework of the
Verleur and Barker model upgraded by authors [2]. In
addition, the authors’ original methodology was applied.
The final version of this upgraded interpretation model
for optical TO-phonon spectra includes the following
Lorentzian parameters: Si, TOi and i representing a
generator capacity, phonon line frequency, and a
damping factor, respectively.
This model has been used to interpret a large number
of phonon spectra for many semiconductor compounds
such as Hg1-xZnxTe, Hg1-xCdxTe, ZnxCd1-xTe, Hg1-xyZnxCdyTe, Hg1-x-yMnxCdyTe with different compositions
to determine parameters Si, TOi and i of each existing
mode. Phonon spectra with mercury vacancies obtained
for some Hg1-xCdxTe and Hg1-xZnxTe compounds were
examined and interpreted using the pseudo-quad model
[3].
The most remarkable success is experimental
observation of the returnable electron-phonon interaction
by measuring the phonon spectra obtained with the
synchrotron. Measurements of the temperature
dependence of phonon modes made with exceptional
thoroughness and accuracy (typical spectral frequency
was 1 cm-1, and 2 cm-1 in some cases) revealed the
discontinuity effect in the Cd0,115Hg0,885Te sample (see
Fig. 1). It refers to how the frequency of HgTe-like and
CdTe-like TO-phonon modes depends on temperature at
the point of forbidden zero crossing (defined as
g≡, the so-called Dirac point [4]). These
discontinuities are resonant. Similarly, this phenomenon
was observed in the Zn0,1Hg0,9Te sample, in which we
also deal with the Dirac point. In this sample, the
discontinuity of the dependence of phonon mode
Figure 1. Plot of the frequency positions in the wave number vs
temperature range of the HgTe-like and CdTe-like [4].
The most recent research made by the Polish-Italian team
is concentrated on a general analysis of phonon spectra
of mercury-containing compounds, for example
Hg1-xZnxTe and Hg1-xCdxTe, taking into account their
composition and temperature[7]. A generalization of the
theoretical temperature shift of the phonon mode
frequency as an analytic equation is derived. It includes
both the anharmonic contribution and the electronphonon e-p interaction which is returnable in this case the electron subsystem effect on the phonon one. Data
show that our equation satisfactorily describes the
temperature shift of both Hg0.885Cd0.115Te and
Hg0.90Zn0.10Te containing Dirac point, although one of
the two constants describing the anharmonic shift of the
HgTe-like mode should be positive that is abnormal too.
In the case of the Hg0.80Cd0.20Te and Hg0.763Zn0.237Te
solid solutions, the role of the returnable e-p contribution
is negligible, but a positive temperature shift for the
HgTe-like modes occurs. This result does not explain the
positive temperature shift of these modes merely by the
contribution of the (e-p) interaction. Indeed, the
relativistic contribution to the chemical bonds induces an
abnormal temperature shift of the electron states in Hgbased semiconductors. The effect is expected since the
Hg d spin-orbit split contribution to chemical bonds may
lead to an abnormal temperature shift of the HgTe-like
modes.
___________________________________________________
[1] M. Cestelli Guidi et al., J. Opt. Soc. Am. A 22 (2005)
2810.
[2] J. Cebulski et al., Phys. Stat. Sol. B 250 (2013) 1614.
[3] J. Cebulski et al., Appl. Phys. Lett. 92 (2008) 121904.
[4] E. M. Sheregii et al., Phys. Rev. Lett. 102 (2009) 045504.
[5] E. M. Sheregii et al., Chin. J. Phys., 49 (2011) 214.
[6] H. Kawamura et al., Solid State Commun. 14 (1974) 259.
[7] M. Woźny et al., J. Appl. Phys. 117 (2015) 025702.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-09
started. This important activity will continue until the
start of operation. Further important developments
concern the X-ray detectors, synchronized optical lasers,
sample environments and the data acquisition and storage
systems.
By summer 2016 the accelerator construction and
installation will be completed and commissioning with
beam will be started at electron energy of 17.5 GeV. By
the end of 2016 the electron beam and the undulators
shall be ready for first generation of FEL radiation. In
2017 the commissioning of the electron beam, the
undulator and FEL operation, and of the science
instruments will continue. The three FEL sources and the
six science instruments will be taken into operation in the
sequence SASE1 – SASE3 – SASE2 over a period of
about four to six months. In parallel, in 2017 first user
experiments will be performed. Full performance of
accelerator, FEL radiation and science instruments shall
be reached in 2018. It is currently planned to increase the
hours for accelerator operation dedicated to the user
program from 1000 hrs in 2017, over 2000 hrs in 2018,
to the final 4000 hrs in 2019.
In the presentation the current layout of the facility
and of the scientific instruments will be discussed. Major
instrumentation efforts will be presented and an outlook
to the commissioning of the facility and the initial
science program will be provided.
Thu. 03. 09., 0900-0940
Status and science program of the European
XFEL
W. Gawelda* on behalf of the European XFEL GmbH
European XFEL GmbH, Albert-Einstein-Ring 19, 22761
Hamburg, Germany
Keywords: X-ray free-electron laser
*e-mail: [email protected]
The European X-Ray Free-Electron Laser (European
XFEL) is currently under construction in the Hamburg
metropole area, Germany. First electrons have been
generated in the laser-driven injector and commissioning
of the injector with beam will commence in autumn
2015. The production and the installation of the main
superconducting accelerator, provided to a large extent
through contributions by partners from a large number of
countries, is in full swing. The 91 undulator segments to
be installed for the various FEL sources have been
produced, tested and are ready for installation. The
challenging X-ray optics and diagnostics elements are
under procurement and first components have been
installed in the tunnels.
At the same time, the design of the scientific
instruments is largely complete and the installation has
__________________________________________________
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-10
At such a fluence the temperature of the material reaches
phase transition point. Secondly, for a high repetition
sources, like in the lithographic applications, the heat
load on optics may reach kW level. This leads to the
optics heating and its destruction, e.g. due to the
enhanced atomic diffusivity in multilayer reflecting
coating. Furthermore repeatable irradiations of optics
may cause multi shot damage, e.g. related to thermal
stresses. Moreover a rapid deposition of EUV pulse
energy at the optics surface causes its hydrodynamical
deformations what results in wavefront distortions for the
proceeding pulses [4].
In my talk dominant processes that lead to the
structural and electronic changes of solid materials under
irradiations with intense femtosecond pulses of X-ray
radiation will be presented. Characteristic time scales of
these processes in a relation to the main materials nad
radiation paremeters like pulse intensity, photon energy,
radiation absorption depth, repetition rate of the source
etc. will be discussed.
Thu. 03. 09., 0940-1020
Phase transitions in solids under irradiations
with x-ray free electrons lasers – characteristic
time scales
R. Sobierajski *
Institute of Physics, Polish Academy of Sciences, Al. Lotników
32/46, PL-02-668 Warsaw, Poland,
Keywords: free-electron laser
*e-mail: [email protected]
The presentation is related to the development of
presently most sophisticated 4th generation synchrotron
radiation sources – the short-wavelength free electron
lasers (FELs). With the advent of the XFEL sources, a
unique combination of radiation properties created new
research possibilities. Radiation intensity produced in
FELs, reaching the values of 1020 W/cm2, exceeds by
many orders of magnitude intensities available from
other monochromatic X-ray sources, thus making it
possible to excite a solid material through phase
transition points up to, so called, warm dense matter
condition. As typical pulse duration, on the order of
femtoseconds, is shorter than most of the time constants
related to structural transformations and to the energy
transfer, it is possible to separate the processes from
influence of radiation absorption during the pulse
duration. Moreover, the photon energies, larger than
value of energy gap in any material makes it possible to
avoid nonlinearities in absorption what radically
simplifies the modeling of the subsequent physical
processes. Thus systematic studies of structural changes
in materials, their electronic properties, as well as
transition dynamics and energy transfer processes are
possible. They can lead to better understanding of the
material’s properties like radiation hardness and to
validation of the existing theoretical models of the
energy transport in solids (see Figure 1).
However, properties of the intense FEL beam create,
apart from new experimental opportunities, the extreme
demands to optical elements applied in the experimental
equipment. The radiation load imposed on optical
elements served for beam diagnostics, controlling and
shaping can lead to their damage. Such materials are of
special interest for studies of radiation hardness. It has
been shown that optical coatings are destroyed by single
FEL pulses if the beam’s intensity/fluence exceeds a
critical level – single shot damage threshold [1-3].
Figure 1. Simulations of the heat diffusion in Si sample
irradiated with 1 ps pulse of XUV radiation at normal
incidence. Plot shows temperature color-map as a function of
depth and time.
Acknowledgments: This work has been partially supported by
the Polish National Science Center
(Grant No. DEC-2011/03/B/ST3/02453)
___________________________________________________
[1] A. Aquila, R. Sobierajski et al., Appl. Phys. Lett. (2015)
[2] J. Gaudin et al., Phys. Rev. B 86 (2012) 024103.
[3] A. R. Khorsand, R. Sobierajski et al., Opt. Exp. 18 (2010)
700.
[4] J. Gaudin et al., Opt. Exp. 19 (2011) 15516.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-11
surface and bulk impurities into tetradymite
semiconductors of Bi2Se3-xTex family by means of soft
X-ray absorption and dichroism.
We show how, depending on adatom/substrate type,
different types of magnetic anisotropy – either uniaxial
out-of plane or basal ion-plane easy axis – may be
achieved [1-2]. Moreover, we discuss the intriguing
oscillatory effects in electron yield detected XAS and its
linear natural dichroism (XNLD) spectra, that are
tentatively ascribed to X-ray induced plasmon excitations
of well-defined frequency.
By exploring evolution of electronic and magnetic
properties of impurities we aim for revealing, how robust
against magnetic impurities is the metallic state at the
surface of canonical topological insulators, and how the
extraordinary topology of electronic structure promotes
the magnetic interactions.
Based on the experience gained during realization of
the project, we discuss the requirements for future
undulator-based soft X-ray absorption and magnetic
dichroism beamline at “Solaris”, that are essential for
probing interactions and electronic structure of ultradiluted magnetic impurities in exotic systems.
Thu. 03. 09., 1140-1220
Magnetic impurities in the bulk and on the
surface of 3D topological insulators probed using
soft X-ray spectroscopy
M. Waśniowska1, M. Sikora2,3*, M. Dobrzański2,
I. Miotkowski4, T. Eelbo5, Z. Kąkol2, A. Kozłowski2
für Experimentelle und Angewandte Physik,
Christian-Albrechts-Universität zu Kiel, Germany
2Faculty of Physics and Applied Computer Science, AGH
University of Science and Technology, Krakow, Poland
3Academic Centre for Materials and Nanotechnology, AGH
University of Science and Technology, Krakow, Poland
4Department of Physics, Purdue University,West Lafayette,
Indiana, USA
5Institute of Applied Physics,University of Hamburg, Germany
1Institut
Keywords: XAS, SXMCD, topological insulators, magnetic
impurities,
*e-mail: [email protected]
Among the most important requirements for
realization of versatile spintronic devices is a foundation
of robust sources of the spin-polarized carriers. For
semiconductors, this is achieved by means of an injection
of spins directly from ferromagnetic material or by
realizing magnetic semiconductors by means of diluted
3d transition metal (TM) impurities. The latter might also
be realized in 3D-topological insulators (TI), in which
the metallic surface states revealing the linear dispersion
in a form of a Dirac cone, are robust against nonmagnetic impurities.
In this contribution we present results of systematic
investigations of electronic and magnetic properties of
Acknowledgments: ESRF (Grenoble), UVSOR (Okazaki), and
LNLS (Campinas) are acknowledged for providing beamtime.
We are gratefull to J. C. Cesar, D. de Souza, K. Kummer,
P. Kuświk, Y. Takagi, and F. Yakhou for their kind help during
synchrotron experiments and sharing experience in operating
SXMCD beamlines. MS acknowledges support from the grant
of National Science Center of Poland (2014/14/E/ST3/00026).
___________________________________________________
[1] T. Eelbo, M. Sikora, G. Bihlmayer et al., New J. Phys. 15
(2013) 113026.
[2] T. Eelbo, M. Waśniowska, M. Sikora et al., Phys. Rev. B
89 (2014) 104424.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-12
–
Stable source of radiation which allows for coaddition of many spectra.
– Source of high power which allows minimization of
the gas pressure and study of weak transitions.
– Very long Maximal Optical Path Difference
(MOPD) in Michelson interferometer.
These conditions are best fulfilled by Fourier
Transform Infrared spectrometers connected to
synchrotron light sources. The power of a synchrotron
light source in the infrared range is 20 times higher then
that of a thermal Globar source. Thus, the aperture can be
reduced from 1.5 to 0.9 mm leading to narrower lines. In
FTIR spectrometer the resolution is determined through
MOPD
(Δνu=0.61/dMOPD),
which
in
standard
spectrometer is equal to 2.5 m. In 8 existing synchrotron
setups MOPD is extended to 9.8 m, and in Swiss Light
Source up to 11.7 m. Thus, the best unapodized
resolution at SLS is 0.00053 cm-1 [1].
This feature of the SLS spectrometer allow for
analysis of fully resolved spectra of heavy molecules
such as naphthalene and indole [2].
New spectrometer allows to study very week
transitions in the spectral region which rarely visited
using previous IR or mmw experimental techniques.
Recently, at SLS the spectrum in the torsional region
(26-100 cm-1) of nitromethane was recorded for the first
time. The torsional band is extremely weak, four order of
magnitude weaker than other fundamental bands. The
spectrum is being analyzed with a specialized software
LWW (Loomis-Wood for Windows) developed in
Poznań. First analysis reveals a number od Q branches.
The assignment work is in progress.
Thu. 03. 09., 1220-1300
High Resolution Molecular Spectroscopy using
synchrotron light source
M. Kręglewski*
Adam Mickiewicz University, Faculty of Chemistry, Poznań,
Poland
Keywords: HRMS, synchrotron IR source, nitromethane,
*e-mail: [email protected]
High Resolution Molecular Spectroscopy in gas
phase is the main source of information about remote
objects. High resolution means that vibrational molecular
spectra are rotationally resolved. For floppy molecules
the spectra can be more complex due to tunneling
splitting. The heavier the molecule the smaller are its
rotational constants and the spectra may be heavily
congested.
The successful recording of high resolution spectra
requires that several exeperimental conditions are
fulfilled:
– The gas pressure is low, usually below 1 mbar.
– The path length is long; the White-type multiple
reflection cells are used.
– The source of IR radiation is stable in time and
covers the whole spectral range .
– The noise level is small.
For many years Fourier Transform Infrared
Spectrometers are used as the main instrument to record
high resolution spectra. The standard spectrometers have
resolution of 0.02 cm-1. Typically, about hundred spectra
are co-added to improve a signal/noise ratio. The analysis
of high resolution spectra requires usually application of
advanced software.
Since high resolution spectroscopy brings important
information about structure and dynamics of molecules
in different vibrational states,there is an obvious
expectation to apply this method to heavier molecules
and molecules of the complex internal dynamics due to
conformation changes. In such cases the experimental
requirements become even more demanding, because of
two main reasons:
– The density of lines is very high, often exceeding
400 lines/cm-1.
– The pressure broadening of individual lines must be
minimized.
– The spectrometer able to record very dense and
weak spectra must have following features:
Figure 1. The Q-branch of nitromethane in the spectrum
recorded at Swiss Light Source.
______________________________________________
[1] S. Albert, K. Keppler Albert, M. Quack in Handbook of
High Resolution Spectroscopy, Vol. 2 (Eds.: M. Quack,
F. Merkt, Wiley, Chichester, 2011, pp. 965–1019).
[2] S. Albert, K. Keppler Albert, P. Lerch, M. Quack, Faraday
Discussions 150 (2011) 71-99.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
L-13
inclined, circular, elliptical; higher harmonics at the
sample <1%; spot size on the sample 300 x 30 μm2.
Thu. 03. 09., 1600-1640
UARPES -Angle Resolved Photoelectron
Spectroscopy beamline at National Synchrotron
Radiation Centre SOLARIS
Elliptically polarizing, APPLE-II type undulator is
the UV radiation source. The undulator has quasiperiodic geometry for suppression of unwanted
harmonics in its radiation spectrum. It is capable of both
parallel and antiparallel modes of operation ensuring the
full control over the light polarization.
The beamline monochromator is combining normal
(NIM) and grazing incidence (PGM) optics, similarly to
recent implementation at SLS [12]. The NIM mode is
indispensable for additional harmonics rejection, where
they are particularly abundant, i.e. at the lowest photon
energies. The NIM mode is designed to be used in the
energy range 8 – 30 eV while the PGM mode in the
energy range 25 – 100 eV.
The experimental endstation is composed of several
ultrahigh vacuum chambers designed for sample
processing and analysis, as well as devices for the sample
storage and transfer. Cryogenic, 5-axes manipulator is
capable of stabilizing the sample temperature in the
range 10 – 500 K, as well as of precise positioning of the
sample surface for experiments. State-of-the-art electron
energy spectrometer, having energetic resolution down to
1 meV, is capable of massively parallell recording of
angle-resolved data spectroscopic data. Low energy
electron diffractometer (LEED), with MCP image
amplifier, is available for the sample positioning and
surface structure studies. Processing devices allow for
typical in situ sample surfrace preparation techniques
such as sputter cleaning, thermal annealing, thin film
growth, sample cleaving, surface reactions in the gas
phase. Sample surface composition and crystallographic
order may be monitored during preparation processess
using combined LEED/AES device.
J. J. Kolodziej1,2*, K. Szamota-Leandersson2
1Faculty
of Physics, Astronomy and Applied Computer Science,
Jagiellonian University, Kraków, Poland
2National Synchrotron Radiation Centre SOLARIS, Krakow,
Poland
Keywords: angle resolved photoelectron spectroscopy,
synchrotron radiation, synchrotron facilities
*e-mail: [email protected]
Angle
Resolved
Photoelectron
Spectroscopy
(ARPES) allows for measurements of fundamental
quantities describing a photoelectron state in space, i.e.
the energy (E) and the momentum (k). If a spin selector
is used additionally, a complete set of quantum numbers
for the electron may be obtained. Than, within a so called
sudden approximation, the electron energy, momentum
and spin measured over the sample surface may be
related, to binding energy, quasimomentum, and spin,
that the electron had in the solid before the photoelectric
event took place. Thus the electronic band structure of
the studied solid is obtained experimentally. Beside this
simple picture ARPES gives also detailed insights into
complex electron – electron and electron – lattice
interactions in the solid.
Many recent advances in materials science have been
enabled by better understanding of the electronic structure of complex systems, gained due to ARPES studies.
Examples include advances in fields such as high temperature superconductivity, topological insulators, graphene physics [1-15].
The importance of the ARPES technique for contemporary science and technology is widely recognized.
Dedicated ARPES beamlines exist at almost all synchrotron radiation centers worldwide. Typically, for these
beamlines, demanded beamtime many times surpasses
the offered one. To meet the predicted demands a beamline dedicated for Angle Resolved Photoelectron Spectroscopy is constructed at SOLARIS synchrotron facility.
It has been given an acronym UARPES (after Ultra
ARPES).
___________________________________________________
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
The UARPES beamline has been designed to have the
following performance: energy range of 8-100 eV;
resolving power ≥ 20 000 over the full energy range;
photon flux on the sample ≥ 5x1011 photons/[email protected]
RP; available polarizations: vertical, horizontal,
19
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J. Maletz et al., Phys. Rev. B 89 (2014) 220506.
S. Ideta et al., Phys. Rev. 89 (2014) 195138.
A. A. Kordyuk, Low Temp. Phys. 40 (2014) 286.
D. Ootsuki et al., J. Phys. Soc. Jap. 83 (2014).033704.
Y-J. Chang et al., Phys. Rev. Lett. 111 (2013) 126401.
H. M. Benia et al., Phys. Rev. B 91 (2015) 161406.
N. Xu et al., Phys., Rev. B 90 (2014) 085148.
M. Hashimoto et al., Nature Physics 10 (2014) 483.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-01
section for Ce 4f electrons. The studies with 40 eV
revealed a Kondo peak (f5/21 final state) and its spin-orbit
partner (f7/21 final state). Two bands crossing Fermi
energy were found in the experiment, one of them has
parabolic dispersion and is considered as a surface state.
The second one forms an electron pocket in the Γ point.
Band structure of stoichiometric Ce2CoSi3 was
calculated with full-potential local-orbital (FPLO) code.
The dispersions from ARPES, which are attributed to
bulk states were found in the calculations.
The Kondo peak is nondispersing at T = 25 K but its
intensity varies considerably with momentum. Its
maximum of the intensity corresponds to a Fermi vector
of the band found in the FPLO calculations, a dispersion
of which was not revealed by ARPES. For the other
Fermi vectors Kondo resonance is of moderate or lower
intensity. The variation of a Kondo peak intensity along a
Fermi surface is in line with the theory predicting a
strong anisotropy of hybridization between f-electrons
and conduction band (Vcf) [3-5].
Tue. 01. 09., 1140-1200
Momentum dependence of a Kondo resonance
in Ce2Co0.8Si3.2
P. Starowicz1*, R. Kurleto1, J. Goraus2, H. Schwab3,4,
M. Szlawska5, F. Forster3,4, A. Szytuła1, I. Vobornik6,
D. Kaczorowski5, F. Reinert3,4
1M.
Smoluchowski Institute of Physics, Jagiellonian University,
Lojasiewicza 11, 30-348 Kraków, Poland
2Institute of Physics, University of Silesia, Uniwersytecka 4,
40-007 Katowice, Poland
3Universität Würzburg, Experimentelle Physik VII, Am
Hubland, D-97074 Würzburg, Germany
4Karlsruher Institut für Technologie KIT, Gemeinschaftslabor
für Nanoanalytik, D-76021 Karlsruhe, Germany
5Institute of Low Temperature and Structure Research, Polish
Academy of Sciences, P.O. Box 1410, 50-950 Wrocław, Poland
6CNR-IOM, TASC Laboratory, SS 14, km 163.5, I-34149
Trieste, Italy
Keywords: Kondo resonance, angle-resolved photoemission
spectroscopy, cerium intermetallics
Acknowledgments: This work has been supported by the
Ministry of Science and Higher Education in Poland within the
Grant no. N N202 201 039. A part of the measurements was
carried out with the equipment purchased thanks to the
European Regional Development Fund in the framework of the
Polish Innovation Economy Operational Program (contract
no. POIG.02.01.00-12-023/08).
___________________________________________________
*e-mail: [email protected]
Ce2Co0.8Si3.2 is a Kondo lattice system with the
Kondo and coherence temperatures equal 50 K and 80 K,
respectively. It crystallizes in a hexagonal structure,
which is a derivative of the AlB2 type. The system
remains nonmagnetic down to 0.4 K and shows increased
electronic specific heat, which amounts to C/T=200
mJ/(moleCe K2) at low temperature (0.4 K). An evidence
of Griffiths phases was found in Ce2Co0.8Si3.2 below 10 K
and is attributed to a disorder in the Co-Si sublattice.
Band structure of Ce2Co0.8Si3.2 was studied by means
of angle-resolved photoemission spectroscopy (ARPES)
at the APE beamline located at Elettra synchrotron [2].
The data were collected at temperature of 25 K with
photon energies of 25 eV and 40 eV, which correspond,
respectively to a low and high photoionization cross
[1] M. Szlawska, D. Kaczorowski, J. Phys.: Condens.
Matter 26 (2014) 016004.
[2] P. Starowicz, R. Kurleto, J. Goraus, H. Schwab,
M. Szlawska, F. Forster, A. Szytuła, I. Vobornik,
D. Kaczorowski, F. Reinert, Phys. Rev. B 89 (2014)
115122.
[3] H. Weber, M. Vojta, Phys. Rev. B 77 (2008) 125118.
[4] J. H. Shim, K. Haule, G. Kotliar, Science 318 (2007)
1615.
[5] P. Ghaemi, T. Senthil, P. Coleman, Phys. Rev. B 77
(2008) 245108.
20
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
form ‘N-mers’ which is followed by transition to Mnrich areas in GaAs matrix, like inclusions.
In order to determine the electronic and atomic
structure around Mn atoms the XAFS spectra at the Kedge of Mn were gathered at the BL22 CLÆSS beamline
at ALBA synchrotron light facility [4]. Figure 1 presents
normalized XANES spectra around Mn K edge and an
inset shows modulus of Fourier transforms, FT(R), of the
EXAFS function for the samples.
The quantitative analysis of XANES and EXAFS of
the “as-grown” sample indicates that Mn atoms most
likely substitute Ga atoms in the GaAs matrix. For the
annealed samples, a dramatic decrease of the amplitude
of FT(R) function can be satisfactory explained by
changing in either of these highly correlated parameters:
an increase in Debye-Waller factor (accounting for
structural and thermal disorder) will result to the same
effect as a decrease in number of the atoms in
corresponding coordination shell, e.g. by forming As
vacancy/ies around Mn atom in the 1st shell. To test the
latter hypothesis a possibility to form a specific type of
point defect including, for instance, VAs, MnGa, and their
combinations, was estimated by calculating their
formation energies using Quantum Espresso DFT code.
The structures with the defects with the lowest formation
energies were used by FEFF8 multiple-scattering code to
calculate theoretical XANES spectra. It was found that
reasonable combination of several theoretical spectra
provide good qualitative agreement with the
experimental ones. In addition, as the hypothesis directly
implies the existence of vacancies in (Ga,Mn)As,
positron annihilation measurements are planned to
estimate type and amount of vacancies in the samples
allowing to correlate them with the observed by XAFS
effects.
Tue. 01. 09., 1200-1220
Structural evolution of (Ga,Mn)As thin film
during medium temperature post growth
annealing manifested by XAS
Y. Melikhov1, J. Sadowski2, P. Konstantynov1,
M. Chernyshova3, J. Domagala1, T. Wojciechowski1,
I. N. Demchenko1
1Institute
of Physics, Polish Academy of Sciences, Warsaw,
Poland
2MAX IV Laboratoriet, Lund, Sweden
3Institute of Plasma Physics and Laser Microfusion, Warsaw,
Poland
Keywords: (Ga,Mn)As, DMS, annealing, DFT, multiplescattering, EXAFS, XANES
*e-mail: [email protected]
Intesity [arb. units]
An extensive research is currently being conducted to
develop a diluted magnetic semiconductor (DMS) with
room temperature ferromagnetism and proper transport
properties, qualities desired for future spintronics
devices. (Ga,Mn)As is the most studied DMS material
and with the optimized MBE growth and post growth
annealing procedures the Curie temperature, TC, as high
as about 200 K has been achived, see, e.g., [1] where the
results of different heat-treatment conditions are
presented. A comprehensive understanding of the
microstructure evolution on transformation processes
(including formation and migration of point defects)
which occur in (Ga,Mn)As during growth and post
growth annealing could potentially lead to a further
progress in reaching higher TC. The goal of this work is
to add to this understanding by checking the
effectiveness of X-ray absorption spectroscopy as a
probe of structural evolution of (Ga,Mn)As after medium
temperature post growth annealing (up to 450 oC).
The (Ga,Mn)As layer was grown in a SVTA MBE
system [2] on GaAs (100) substrate with thin AlAs buffer
layer. An amorphous As capping layer was deposited on
(Ga,Mn)As at the end. After removing from the MBE
setup, the film was cleaved into three pieces: one piece
was left intact and the other two were annealed at
temperatures 350 oC and 450 oC. After conventional
initial analysis, the (Ga,Mn)As layer was separated from
the GaAs substrate on all samples by chemical etching, a
so-called “lift-off” procedure [3], in order to avoid
disturbance of X-ray absorption measurements by Bragg
scattering of the bulk GaAs substrate at defined values of
energy of incident beam.
The content of Mn in the Ga1-xMnxAs layer was
estimated to be ~1 at.% by Energy-dispersive X-ray
spectroscopy (EDX) using Auriga 40 FIB-SEM
workstation. High resolution diffraction studies were
performed using a Philips X’Pert-MRD diffractometer
equipped with a parabolic X-ray mirror, a four-bounce
Ga 220 monochromator at the incident beam, and a
three-bounce Ge analyzer at the diffracted beam. The
qualitative analysis of ω/2θ scans obtained for the
symmetric (004) reflection for the annealed samples
allows to manifest the structural reorganization in
(Ga,Mn)As film. It is assumed that initially Mn atoms
Mn K edge
XANES:
as grown
annealed at (oC):
350
450
Ga1-xMnxAs
x ~ 1 at.%
|(R)| [Å-2]
O-02
1
2
3
4
5
R [Å]
6530
6535
6540
6545
6550
6555
6560
Photon energy [eV]
Figure 1. Normalized Mn K-edge XANES spectra of the
(Ga,Mn)As layers. The inset shows Fourier transforms of the
k1-weighted Mn K-edge EXAFS χ function.
Acknowledgments: This work was supported by the Baltic
Science Link project coordinated by the Swedish Research
Council, EAgLE project (Project Number: 316014), CALIPSO
program and PL-Grid and ICM infrastructures.
_____________________________________________________________________________
[1] M. Wang et al., Appl. Phys. Lett. 93 (2008) 132103.
[2] J. Sadowski, J. Z. Domagala, chapter 2 in Advanced
Functional materials: A perspective from theory to
experiment (Eds. B. Sanyal and O. Eriksson; Elsevier,
2012).
[3] S. Decoster et al., J. Synchrotron Rad. 20 (2013) 426.
[4] ALBA light source, Spain, http://www.cells.es/.
21
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-03
the ZnO/Cu2O may be produced at ambient conditions.
ZnO has been a preferred candidate of window layer of
solar cell because of its wide and direct band gap
of 3.37 eV at room temperature, good diode
characteristics in the dark especially its very high
photocurrent [7].
Tue. 01. 09., 1220-1240
Fabrication and characterization of multilayer
solar cells
M. Pławecki
Institute of Materials Science, University of Silesia, 75 Pułku
Piechoty 1A, 41-500 Chorzów.Poland
Keywords: zinc oxide, cuprous oxide, solar cell
*e-mail: [email protected]
The solar cells based on copper oxide and zinc oxide
are a promising alternative to conventional silicon cells
because of the relatively low cost of production and the
theoretical efficiency of approx. 16% [1-3].
First of all, this paper focuses on the characteristics of
the ZnO layer - n-type, and Cu2O/CuO - p-type
semiconductors prepared by electrodeposition, which
allows to create transparent semiconductor layers with
good optoelectronic properties [4].
Secondly, fabrication of perovskites layers which acts as
light absorber [5].
Perovskites having the composition of CH3NH3PbX3
(X = I, Br) are examined as an attractive absorbing
materials for use in low cost solar cells with high
efficiency. For about five years, there has been an
increase in energy conversion efficiency of these
materials, which shows remarkable potential of their
usage. However, in most devices, including thin-film
simplest planar structure identifying the basic working
mechanisms, which are still being debated, will be
crucial to design the optimum device configuration and
maximize solar cell efficiencies. Combining different
methods of production with relatively low cost such as
spin coating for perovskite and electrolytic deposition for
metal oxides semiconductors provides possibility to
create multifunctional layers and improve efficiency and
reduce cost of solar cells. Cu2O layers were prepared on
pre-cleaned Fluorine doped Tin Oxide (FTO) glass plate
by electro deposition using platinum as counter
electrode, ZnO layers were galvanostatically electrodoposited and CH3NH3PbX3 was spin-coated under
100°C.
Cuprous (I) oxide (Cu2O) semiconductors are a
promising candidates of an all functional-oxide solar cell
material because of its photo electronic properties such
as proper energy band gap of 2.1 eV, environmentally
friendly properties such as non-toxicity and low material
cost [1,2]. It was proven that a solar cell devices based on
.
Figure 1. Concept of solar cell with perovskite absorber.
All the crystalline components in the Cu2O and ZnO
thin films were investigated by XRD, diffraction peaks
corresponding to Cu2O and ZnO were observed in thin
films, which consisted of cupric phase with monoclinic
system. It was shown that the solar cell devices have the
structures of crys-Cu(001)/p poly-Cu2O/Ag and polyCu/p-poly-Cu2O/Ag, which convert solar energy into
electrical energy. Additianal the layers deposited on FTO
were studied by XPS measurements. The core levels
S 2p, Cu 2 p, O 1s, C 1s, Zn 2p spectra and the Cu Auger
spectrum were measured. During formation of the layer
on the surface of FTO all processes proceed in an open
medium; therefore, it is not possible to avoid ambient
effects. Since the surface of this layer is active, it adsorbs
oxygen, water, and other contaminants. Therefore the
surface of the layer can differ from the macrostructure
and chemical composition of the entire layer. Finally the
analysis of the current–voltage characteristics was
applied to determine the values of electrical parameters
of the solar cells [6,7].
___________________________________________________
[1] Kazuya Fujimoto, Takeo Oku et al., Journal of Physics:
Conference Series 433 (2013) 012024.
[2] S Noda, H Shima et al., Journal of Physics: Conference
Series 433 (2013) 012027.
[3] V. Popescu, et al., Phys. Rev. B 78 (2008) 205321.
[4] O. Breitenstein, Electronics Review 21 (2013) 259.
[5] M. M. Lee et al., Science 338 (2012) 643.
[6] A. Boudghene Stambouli, E. Traversa, Renewable and
Sustainable Energy Reviews 6 (2002) 297.
[7] C. H. Hsu, L. C. Chen, Y. F. Lin, Materials 6 (2013)
4479.
22
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-04
The valence band spectra measured -in and -off
resonance was presented in figure 2. Small changes at
localization of B feature are visible.
Tue. 01. 09., 1240-1300
Intensity (a.u.)
Application of X-ray absorption and resonant
photoemission spectroscopy to study electronic
states of iron through 3p-3d transition for
SrTiO3:Fe epitaxial film
J. Kubacki1,2*, D. Kajewski2, A. Koehl3, Ch. Lenser3,
R. Ditmann3, J. Szade1,2
a)
48
3 4
2
50
5
52
A
Normalized Intensity
Silesian Center for Education and Interdisciplinary Research,
75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
2 A. Chelkowski Institute of Physics, University of Silesia,
Uniwersytecka 4, 40-007 Katowice, Poland
3 Peter Grünberg Institut, JARA-FIT, Forschungszentrum
Jülich, 52425 Jülich, Germany
Keywords: X-ray absorption, resonant photoemission,
strontium titaniate, doping by iron
6
5
4
3
2
1
*e-mail: [email protected]
12
The strontium titanate STO is promising material for
electronic application. The electrical properties of this
material can be tuned by iron doping.
The synchrotron radiation was used to study of
SrTiO3 doped by 2% of iron thin film. As was shown in
our earlier work the oxidation states of iron in the
STO:Fe thin films is in a mixture of Fe2+ and Fe3+
states [1]. In order to confirmation and distinguish
oxidation states of iron at sub-surface layer of the film
we performed X-ray absorption study in range of the Fe
M-edge threshold.
The pure SrTiO3 is an isolator with a energy gap
of 3.6 eV. The valence band of SrTiO3 contains mainly
O2p-Ti3d hybridized states. The influence of Fe3d
electrons on the density of states in the energy gap was
study by resonant photoemission in range Fe3p-3d
resonance. Measured spectra are compared with the
results obtained for Fe2p-3d resonance [2].
The X-ray absorption spectra obtained for the
Fe M-edge contains two main peaks at 53 eV and
59.6 eV of photon energy. In order to analysis of the
shape obtained curve we performed atomic multiplet
calculation of Fe3p absorption spectra using the
CTM4XAS program [3]. To verify obtained result also
photoemission Fe3p spectra was measured and compared
with calculation.
In figure 1a only a shape of the first peak of
absorption was showed.
The valence band spectra, presented in figure 1b,
were measured in the binding energy range from –3 to
13 eV. We explored the photon energy range across the
Fe3p-3d photoionization threshold (47 eV – 54 eV). Two
features A and B are clearly visible at energy of about
4 eV and 6 eV, respectively. The relative intensity of
observed maxima is changed with energy of photon. The
intensity of B feature increases for the energy of photon
higher than h=53 eV.
54
Photon Energy (eV)
b)
1
1:E=47eV
6:E=62eV
56
B
SrTiO3:2%Fe
ResPES
10
8
6
4
2
0
Binding Energy (eV)
-2
Figure 1. a) Fe M-edge XAS spectra recorded for Fe doped
STO films obtained in AEY mode. b) Photoemission spectra of
the valence band region measured in range of photon energy
corresponding to Fe3p-3d photoionization threshold.
h = 62 eV
Normalized Intensity
h = 53eV
h = 47eV
15
10
5
0
Binding Energy (eV)
-5
Figure 2. The details of valence band spectra measured at
energy of photon –in and –off resonance.
The mixed valence of iron was discussed based on
the X-ray absorption spectroscopy and atomic multiplet
calculation. The influence of Fe 3d state on valence band
STO:Fe film was study by resonant photoemission.
Small difference in shape of valence band was detected
in resonance.
Acknowledgments: This work was supported by
NCBiR/ERA-NET-MATERA/3/2009 project.
___________________________________________________
[1] A. Koehl, Phys. Chem. Chem. Phys. 15 (2014) 8311.
[2] J. Szade et. al., in preparation
[3] E. Stavitski, F. M. F. de Groot, Micron 41 (2010) 687.
23
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Efficient processing of organic polymers (PMMA and
PTFE) has been also demonstrated with the compact
EUV source for metrology, operating at 10 Hz [14] and
strong temperature effect on soft X-ray photo-etching of
PTFE was shown [15]. The same source equipped with
a multi-foil optic collector [16] has been used to study
the EUV emission from solids irradiated with intense
EUV pulses [17]. A new technique for detection of
surface changes of materials, utilizing scattered or
luminescent EUV radiation, was proposed [18].
The use of a grazing incidence axisymmetrical
ellipsoidal mirror as a collector strongly increased the
EUV fluence on irradiated samples up to 100 mJ/cm2
[19]. This made possible to increase dramatically the
EUV ablation rates and improve micromachining of
polymers. Efficient processing of non-organic materials
(SI, Ge, NaCl, and CaF2) has been also demonstrated
[20]. Modification of polymer surfaces by creation of
characteristic micro- and nanostructures was observed in
case of irradiation with EUV pulses at relatively low
fluence (<10 mJ/cm2) [15, 21-25]. It was found that such
EUV patterning of surfaces can be useful for
biocompatibility control of polymers [26]. These studies
resulted in development of the source dedicated for EUV
processing of materials [27].
Laser plasma EUV source for processing is composed
of a vacuum chamber in a form of a vertical column
mounted onto a cubical base, housing a compact
commercial Nd:YAG laser system (EKSPLA) generating
4 ns laser pulses with energy up to 800 mJ and vacuum
pumping system. The source chamber is composed of
three sections. Each section is pumped separately by oilfree vacuum pumps (differential pumping). In the first
upmost section of the chamber the electromagnetic valve
to produce a gas puff target and the laser beam focusing
system are placed. The valve is mounted using the x-y-z
translation stages, allowing placing the gas puff target in
the required position with accuracy of about 10 m. The
gas puff targets are formed by pulsed injection of
working gas (krypton, xenon or krypton/xenon mixture)
into a stream of helium, using an electromagnetic valve
system with a double-nozzle setup. The repetition rate of
the system is determined by the repetition rate of the
laser (10 Hz). The source is equipped with a grazing
incidence axisymmetrical ellipsoidal mirror (RITE), to
focus the EUV radiation. The mirror is mounted in the
second, central section of the vacuum chamber. It makes
possible to focus the EUV radiation onto a polymer
sample mounted in the third section of the chamber,
evacuated to high-vacuum. The EUV radiation is focused
to a spot of about 1 mm in diameter with fluence up to
100 mJ/cm2 for the xenon gas puff target [28].
The source has been used for EUV micromachining
of poly(vinylidene fluoride) (PVDF). PVDF is an
important fluoropolymer because of its piezoelectric,
pyroelectric and ferroelectric properties. It is also known
to have an extremely high chemical stability and
electrical resistivity. Micro- or even nanopatterning of
PVDF is highly desirable for applications in
multifunctional and integrated devices. Many works have
been performed on surface processing of PVDF using ion
beams, synchrotron X-ray and UV laser radiation,
Tue. 01. 09., 1620-1640
Extended abstract
O-05
Laboratory sources of soft X-rays and extreme
ultraviolet (EUV) based on laser plasmas
produced with a gas puff target
H. Fiedorowicz*, A. Bartnik, P. W. Wachulak,
R. Jarocki, J. Kostecki, M. Szczurek, D. Adjei,
I. U. Ahad, M. G. Ayele, T. Fok, A. Szczurek,
A. Torrisi, Ł. Węgrzyński
1Institute
of Optoelectronics, Military University of Technology,
Kaliskiego 2, 00-908 Warsaw
Keywords: lasers, laser plasmas, laser plasma sources
*e-mail: [email protected]
Electromagnetic radiation in the soft X-ray and
extreme ultraviolet (EUV) wavelength ranges can be
produced in a high-temperature plasma generated by
interaction of high power laser pulses with matter [1-3].
It was demonstrated that laser plasma soft X-ray and
EUV sources could be useful in various applications in
physics, material science, biomedicine, and technology.
However, conventional laser plasma sources based on
a solid target have debris production problem. We have
demonstrated that using a double-stream puff target,
instead of a solid target, it is possible to develop highly
efficient and debris-free laser plasma soft X-ray and
EUV sources [4-5]. The target is formed by injection of
high-Z gas (xenon, krypton, argon, etc.) into a hollow
stream of low-Z gas (hydrogen and helium) using
a double nozzle. The nozzle setup consists of a central
nozzle in a form of a circular orifice, surrounded by an
outer nozzle in the form of a ring. The nozzle is supplied
with gases from two electromagnetic valves mounted in
a common body. Strong soft X-ray and EUV emissions
from the double-stream gas puff targets, exceeding the
emissions from solid targets, have been demonstrated [6].
In the paper laser plasma sources of soft X-rays and
EUV based on a gas puff target, developed for various
applications, including metrology and microscopy,
photo-etching and processing of materials, surface
modification, radiography and tomography, radiobiology
and material damage, photoionization of gases and cold
plasma formation, are presented.
The gas puff target approach was used for developing
a compact laser plasma EUV source for metrology
applications [7]. The xenon target was irradiated with
4 ns/0.5 J pulses produced with repetition rate of 10 Hz
from a commercial Nd:YAG laser. Conversion efficiency
of the laser energy into the EUV energy at 13.5 nm
wavelength of about 2 % was measured in 7 %
wavelength band, corresponding to about 0.5 % in 2 %
band [8]. The source has been used in the measurements
of optical characteristics of Mo/Si multilayer mirrors [9].
High-brightness soft X-ray source based on the gas
puff target driven with the PALS laser facility [10, 11]
has been used for the first time for processing materials.
Direct photo-etching of inorganic (silicon) and organic
(polymers) materials with nanosecond pulses of soft
X-ray and EUV radiation was demonstrated [12, 13].
24
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
however, irradiation of PVDF with these sources resulted
in strong modification of the molecular structure in a
near-surface layer of the polymer. Using the laser plasma
EUV source dedicated for processing polymers we have
demonstrated for the first time efficient micromachining
of PVDF without changing the chemical structure of the
unprocessed material [29]. PVDF foils of 50 m
thickness (Goodfellow) were irradiated with the EUV
radiation through a contact metal mask with square
orifices 6060 m2. Micro holes etched through the foils
have been obtained as a result of 1 min irradiation at
10 Hz repetition rate.
Investigation of the ablation products with QMS
demonstrated a good agreement between the
stoichiometric composition of PVDF molecules in the
ablated and bulk polymer. XPS spectra, acquired for the
polymer after ablation, are almost identical to the
spectrum of pristine PVDF, indicating preservation of the
chemical structure of the remaining material. However,
XPS measurements performed on the polymer irradiated
with low fluence (<10 mJ/cm2) indicated strong chemical
modification in the near-surface layer. In this case
defluorination and thus carbon enrichment in the surface
material was revealed [29].
We have demonstrated in our previous works that
EUV radiation can be used for surface modification of
polymers for biocompatibility control [26, 30]. Surface
modification of PTFE, PVDF and PC polymers for
biocompatibility control has been studied using the laserplasma EUV source. Modified surfaces were
characterized by SEM and AFM. Up to several hundred
nanometers high wall-type micro- and nanostructures
were formed [31]. Simultaneous treatment of polymer
surface by EUV radiation and ionized nitrogen injected
in the interaction region has been studied [32]. Chemical
analysis by XPS revealed decreased oxygen contents in
PC samples and nitrogen enrichment in PTFE [31, 33].
Exclusion of oxygen from polar groups leads to
a polymer with increased hydrophobicity that was
confirmed
by
contact
angle
measurements.
Biocompatibility tests of PTFE and PVF samples
modified with the EUV photons and seeded with
fibroblasts have shown strong cells adhesion to polymer
surfaces [34].
The compact laser plasma EUV source, additionally
equipped with an ellipsoidal mirror with the Mo/Si
coating and operating with the argon gas puff target,
allowed producing quasi-monochromatic EUV radiation
at 13.8 nm wavelengths [35]. This source has been
successfully used for EUV nanoimaging with the spatial
resolution down to 50 nm, proving possibility to develop
a compact, desk-top EUV imaging tool [36-38]. The tool
was also used for EUV imaging of nanostructures [39],
crystalline thin films and nanofibers [40].
The compact EUV source has been also used for
pulsed radiography and tomography of the gas puff
targets. The beam of EUV radiation for backlighting of a
target under study was produced by spectral selection of
emission from xenon plasma using a Mo/Si multilayer
mirror. To eliminate the visible light from the plasma
a 200 nm thick Zr filter deposited on a 200 nm thick
Si3N4 membrane was used. In this way quasimonochromatic radiation at 13.5 nm wavelength with the
bandwidth of about 1nm was obtained. The EUV
shadowgrams of the targets were registered with the use
of the back-illuminated CCD camera (Reflex), equipped
with a 512512 pixels CCD chip.
The EUV radiography setup was used for
characterization of the multi-jet gas puff targets with
modulated gas density for high-order harmonic
generation (HHG) experiments [41] produced using the
nozzles in a form of linear array of 5, 7 or 9 orifices. 2-D
gas density map for the target produced using the nozzle
with 7 orifices at the backing pressure of 4 bar and
corresponding gas density profiles for various distances
are presented in [42]. The radiography setup with the
laser plasma EUV source has been also used for
characterization of the dual-gas multi-jet gas puff target
[43], the pulsed gas cells [44] developed for HHG
experiments and the elongated plasma channels [45].
The same setup was used for the EUV tomography of
the multi-jet gas puff targets. In this case the gas puff
valve was mounted on top of a rotation stage to ensure
2 rotation of the nozzles while acquiring projections.
The set of 900 EUV projections was used for
tomographic reconstruction. The 3-D image of the multijet gas puff target has been obtained [46, 47]. A new
technique for 3-D tomographic reconstruction of low
density objects with the use of a compact laser plasma
EUV source was demonstrated.
Laser plasma soft X-ray sources operating in the
‘water window’ wavelength range between 2.3 nm and
4.4 nm are used for microscopy of live biological objects.
It was shown that the laser plasma source with argon or
nitrogen gas puff targets is an efficient source of
radiation in this range [48]. This source has been used for
development of a compact, desk-top soft X-ray
microscope, based on a laser plasma source, operating in
the ‘water window’ range. The microscope was equipped
with an ellipsoidal grazing incidence mirror coated with
nickel as a condenser to focus soft X-ray radiation from
the plasma onto a sample [49]. A Wolter type grazing
incidence hyperboloid/ellipsoid axisymmetrical mirror
was used as an objective to form a magnified image onto
a CCD camera. The first soft X-ray microscopy images
in the ‘water window’ spectral range of biological
samples (onion skin cells) with sub-micron spatial
resolution have been obtained [50].
Much better resolution was obtained using a Fresnel
zone plate as a microscope objective. The Fresnel zone
plate was 250 m in diameter, with the outer zone width
of 30 nm and the focal length at 2.88 nm f = 2.6 mm.
Soft X-ray microscopy images of the test object (the
TEM mesh) could be registered in 10 s exposure time
(100 pulses). The spatial rsolution assessed by the knife
edge test was equal to 60 nm. The resolution for a singleshot exposure was about 240 nm [51]. The microscope
has been used for imaging of biological samples.
Soft X-ray images of thin layers of saccharose (160 nm)
and plasmid DNA deposited on the Si3N4 membrane
have been obtained in 20 s and 50 s exposition times,
respectively [51].
25
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
[2] D.T. Attwood, Soft X-rays and extreme ultraviolet
radiation: Principles and applications (Cambridge
University Press 1999).
[3] V. Bakshi, EUV sources for lithography (SPIE Press
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London 2015).
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102.
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The laser plasma soft X-ray source with an argon gas
puff target irradiated with the 4 ns/0.8 J/10 Hz Nd:YAG
laser was developed for application in radiobiology
experiments [52]. The source delivers approximately
6.831013 photons/4π in the wavelength range of about
2.5-4 nm. The low penetration depth of this radiation in
biological samples and pulsed character of the source
lead to high local dose loads and dose rates, respectively.
The design of the source allows samples to be irradiated
both in vacuum and in He-environment. Doses in a single
pulse of soft X-rays of about 300 Gy for irradiation in
vacuum and about 20 Gy for the He-environment
irradiation were measured. Initial irradiation experiments
carried out with plasmid DNA demonstrated that the
source can be used in systematic studies of soft X-ray
radiation damage to biomacromolecular samples and
other biological specimen [53]. The source has been also
used for the soft X-ray contact microscopy experiments
[54].
The laser plasma EUV source for processing of
materials has been also used in the first experiments on
EUV photoionization of atomic and molecular gases.
Gases were injected into the focus of the EUV beam
using an additional gas nozzle mounted in the third
section of the source chamber. Formation of lowtemperature photo-ionized neon plasmas induced by
nanosecond EUV pulses from the laser plasma source
and by femtosecond EUV pulses from the FLASH free
electron laser was studied [55]. Luminescence of helium
and neon gases induced by the EUV pulses was
measured [56] and significant differences between
absorption spectra of neutral helium and low temperature
photoionized helium plasmas have been detected [57].
Spectral investigations in the EUV/VUV region of
photoionized plasmas induced in atomic and molecular
gases using nanosecond EUV pulses were performed
[58].
EUV photoionization of gases and formation of lowtemperature plasmas have been also studied using more
energetic EUV pulses generated as a result of irradiation
of the gas puff target with laser pulses with time duration
from 1 ns to 10 ns and energies from up to 10 J at 10 Hz
repetition rate produced from the Nd:YAG laser system
(EKSPLA) [59]. These preliminary investigations have
shown applicability of compact laser plasma EUV
sources for research in a new field of EUV-induced
plasmas.
Acknowledgments: This work was supported by the EC’s 7.
Framework Program (LASERLAB-EUROPE II - grant
agreement n° 228334 and LASERLAB-EUROPE III - grant
agreement n° 284464, and the Erasmus Mundus Joint Doctorate
programme EXTATIC), the National Centre for Science (award
number DEC-2011/03/D/ST2/00296), and the National Centre
for Research and Development Lider Programme, (award
number LIDER/004/410/L-4/12/NCBR/2013).
_______________________________________________
[1] I.C.E. Turcu and J.B. Dance, X-rays from laser plasmas:
Generation and applications (Wiley 1998).
26
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-06
where the size of the sample is reverse to the attainable
pressure.
The High Pressure Beamline ID09A at the European
Synchrotron Radiation Facility is dedicated to the
determination of structural properties of solids at high
pressure using angle-dispersive-diffraction with diamond
anvil cells. It offers monochromatic diffraction with large
area detectors and provides beam seizes down to 10 x 10
µm at very high photon fluxes. High-pressure powder
and single–crystal data can be collected from ambient
pressure to approximately 200 GPa, as well as at low and
high temperatures.
Several examples illustrating high pressure
crystallographic studies and the research potential of
ID09A are going to be presented.
Wed. 02. 09., 1020-1040
Single-crystal X-ray diffraction at extreme
conditions
D. Paliwoda*, M. Hanfland
European Synchrotron Radiation Facility, B.P.220, F-38043
Grenoble Cedex, France
Keywords: high pressure single crystal diffraction, synchrotron
radiation.
*e-mail: [email protected]
Pressure is one of basic thermodynamic parameters,
however its effect on chemical reactions, properties of
materials and their structure remains relatively poorly
understood, mainly due to the lack of experimental data.
This deficiency of high-pressure information, compared
to the vast amount of low- and high-temperature data, is
due to the technical requirements of high-pressure
experiments. They could be conducted only in strong
vessels with thick walls, capable of withstanding high
pressure, but obscuring access to the sample. The
breakthrough in the high-pressure methods was the
invention of the diamond-anvil cell, DAC [1]. Its design
evolved in the second half of XXth century and finally
made the DAC a powerful tool for in situ spectroscopic
and diffraction investigations.
High pressure crystallography has become an
efficient technique for crystal structure determinations
and for monitoring phase transitions [2,3]. The diamondanvil cell can be nowadays routinely applied in
laboratories and dedicated beamlines of synchrotron and
neutron facilities.
Synchrotrons provided new quality in X-ray
diffraction and particularly in these experiments where
very high intensity of the radiation is needed. It can be
especially advantageous in high pressure crystallography,
Figure 1. Membrane Diamond Anvil Cell (MDAC).
___________________________________________________
[1] C. E. Weir, E. R. Lippincott, A. Van Valkenburg,
E. N., Bunting, J. Res, Natl. Bur. Stand. 63A (1959) 55.
[2] T. Boffa Ballaran, A. Kurnosov, D. Trots, High Pressure
Research, 33 (2013) 453.
[3] M. I. McMahon, High Pressure Crystallography (in
Advanced X-ray Crystallography, Springer-Verlag Berlin
Heidelberg 2012).
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-07
O-08
Wed. 02. 09., 1040-1100
Wed. 02. 09., 1140-1220
High-brilliance X-ray sources: a bright future
for life science studies
SAXS studies of selected flexible proteins or
proteins of modular structure
J. B. Pełka*
M. Kozak*, Z. Pietralik, M, Taube
Institute of Physics, Polish Academy of Sciences, al. Lotników
32/46, 02-668 Warsaw, Poland
1Department
of MaclomolecularPhysics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
Keywords: synchrotron radiation, free electron laser, life
sciences
Keywords: synchrotron radiation, small angle X-ray scattering,
disordered proteins, modular structure
*e-mail: [email protected]
*e-mail: [email protected]
More than twenty years ago, a wide access to 3rd
generation synchrotron radiation (SR) sources has
brought an accelerated growth in studies of a condensed
matter. Unique properties of SR together with countless
improvements both in the experimental and
computational techniques have also opened up new
exciting era, especially in research of the biological
structures and processes. A variety of methods
employed to study biological matter on the levels from
molecules through cells and tissues up to whole
organisms, like X-ray crystallography, spectroscopies in
a broad range of wavelengths from IR up to hard X-rays,
a number of imaging techniques, and many other, have
led to a substantial progress in the life science and
related fields.
The history repeats over the last decade, due to a
rapid development of the short-wavelength Free
Electron Lasers (FELs), new 4th generation SR sources.
They can produce a fully tunable monochromatic
radiation, including hard X-rays, in ultrafast
femtosecond pulses with a peak power up to several
GW. FELs break fundamental barriers that limit all
other known X-ray sources. This means new marvelous
qualities in probing the secrets of life with
unprecedented femtosecond temporal and atomic spatial
resolution. With FELs, it is possible to study even single
macromolecules using enormously large, damaging
irradiation doses and acquire structural information
before the object is damaged. In this way one can
explore both crystals and small nanocrystals and noncrystalline materials.
This talk is aimed at showing, in a short trip across
fascinating areas of high-brilliance X-ray sources, how
plainly is emerging the brightest ever future for
experimental methods. The perspectives emerging from
having to be opened soon the first Polish synchrotron,
SOLARIS, as well as the access to the EU-XFEL
facility in Hamburg, the project developed with
participation of Poland will be also mentioned.
Small angle scattering of synchrotron radiation (SRSAXS) is a technique, which is suitable to the study of
difficult biomacromolecules, and especially the low
resolution structure in solution of the proteins possessing
the flexible or modular structure. Due to the flexibility of
the conformation of these macromolecules, is very
difficult (or nearly impossible) to obtain their atomic
structures based on the classic methods of protein
crystallography. On the other hand, these proteins often
play important physiological functions in which a
flexible conformation of the protein molecule is crucial
for the its function (in regulation, signaling and control
pathways) [1]. The physiological function of flexible
proteins often is complementary to function played by
other ordered protein molecules or protein domains [2,3].
Therefore is very important to have in our disposal a
routine method dedicated to the determination of flexible
structures in solution.
SAXS technique also offers also a substantial support
in the prediction and modelling of protein structure by
the use of bioinformatics. Low resolution structural
protein models in solution, obtained by SAXS, can be
used as templates (molecular envelopes) for docking of
bioinformatics models [4]. As a result, the full molecular
structures, even large proteins or protein complexes, can
be determined [5].
In recent years, SAXS is also used in other
applications, including also the use of low resolution
models to verify NMR structures, or even in
supplementation the NMR data [6].
During the lecture will be presented the applications
of SR-SAXS technique in the study of selected
disordered protein systems, modular proteins, protein
complexes, denaturation processes as well as the
conformational dynamics of macromolecules in solution.
Special attention will be paid on proteins from plant
innate defence systems [7], regulatory proteins and on
the conformational dynamics of proteins involved in
neurodegenerative diseases [8].
Acknowledgments: This research project has been financed by
the funds from the National Science Centre (Poland) granted on
the basis of decision no. DEC-2012/06/M/ST4/00036.
___________________________________________________
[1] V. N. Uversky, Biochimica et Biophysica Acta 1834
(2013) 932.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
[2] A. K. Dunker, J. D. Lawson, C. J. Brown, R. M. Williams,
P. Romero, J. S. Oh, C. J. Oldfield, A. M. Campen,
C. M. Ratliff, K. W. Hipps, J. Ausio, M. S. Nissen,
R. Reeves, C. Kang, C. R. Kissinger, R. W. Bailey,
M. D. Griswold, W. Chiu, E. C. Garner, Z. Obradovic,
J. Mol. Graph. Model. 19 (2001) 26.
[3] H. J. Dyson. P. E. Wright, Nature Reviews Molecular Cell
Biology 6(3) (2005) 197.
[4] D. Schneidman-Duhovny, A. Rossi, A. Avila-Sakar,
S. Joong Kim, J. Velázquez-Muriel, P. Strop, H. Liang,
K. A. Krukenberg, M. Liao, H. Min Kim, S. Sobhanifar,
[5]
[6]
[7]
[8]
29
V. Dötsch, A. Rajpal, J. Pons, D. A. Agard, Y. Cheng,
A. Sali, Bioinformatics 28 (2012) 3282.
H. D. Mertens, D. I. Svergun, J Struct Biol. 172 (2010)
128.
M. Kozak, A. Lewandowska, S. Ołdziej, S. RodziewiczMotowidło, A. Liwo. Journal of Physical Chemistry Letters. 1 (2010) 3128.
M. Taube, J. R Pieńkowska, A. Jarmołowski, M. Kozak,
PLOS ONE 9(4) (2014) e93313.
G. Ranheimer Östner, V. Lindström, P. Hjort Christensen,
M. Kozak, M. Abrahamson A. Grubb. The Journal of
Biological Chemistry 288 (2013) 16438.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-09
In plants and mammals HSP90 protein complex is
involved in the innate immunity by the stabilizing NBLRR (nucleotide binding leucine rich repeats receptors)
receptors that recognizes pathogenic molecules or results
of its action within the cell and triggers immune response
against pathogenic agents [2]. For this function HSP90
protein requires two proteins: SGT1 (suppressor of G2
allele of skp1) and RAR1 (required for MLA12
resistance 1). SGT1 protein consists of three domains: Nterminal TPR domain that is required for dimerization (in
plants and fungi), central CS domain that is responsible
for the interaction with N-terminal domain of HSP90 and
C-terminal SGS domain that is thought to be involved in
the NB-LRR protein binding. RAR1 protein consist of
two zinc finger domains called CHORDs and in
metazoans also CS domain at the C-terminus. Both
proteins have dynamic structure with well folded
domains behaving as rigid bodies and dynamic
unstructured regions between them. Although structure
of the core of the HSP90-SGT1-RAR1 protein complex
is known there is little information about the structure of
the full length complex.
In this work we studied low resolution structure of
the plant HSP90-SGT1 complex with ADP in solution
using small angle X-ray scattering technique. Using
MCR-ALS analysis and ab-initio modeling we found that
in the complex with the HSP90, SGT1ΔSGS protein
exists as a monomer and binds to the HSP90 protein with
the 1:2 stoichiometry. This is unexpected because HSP90
protein has two potential binding sites for SGT1 protein
and TPR domain which is responsible for dimerization
doesn't interact with HSP90 protein. By the studying of
the HSP90 C-terminal truncation variant in the complex
with the SGT1ΔSGS protein we showed that
dimerization of HSP90 is not required for the
dissociation of SGT1ΔSGS protein dimer. We also
showed that binding of the CS domain alone doesn't
change conformation of the HSP90ΔC protein. In the
complex with SGT1ΔSGS protein and ADP molecule
HSP90 protein adopts open conformation. Because
HSP90 protein interacts with many partners at different
steps in client folding proper stoichiometry of the
functional HSP90 complex is important for its function.
Asymmetric binding of its partners may be one of the
ways to prevent improper assembly of the HSP90
complex.
Wed. 02. 09., 1220-1240
Solution structure of the plant HSP90-SGT1
complex with ADP
M. Taube1*, A. Jarmołowski2, M. Kozak1
1Department
of Macromolecular Physics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
2Department of Gene Expression, Institute of Molecular
Biology and Biotechnology, Faculty of Biology, Adam
Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland
Keywords: small angle X-ray scattering, plant-pathogen
interactions, protein structure
*e-mail: [email protected]
Heat Shock Protein 90 kDa (HSP90) protein is a
molecular chaperone that assists the folding of the client
proteins [1]. HSP90 takes part in the last step of this
process using ATP to catalyze transition of the partially
folded substrate to the stable folded state. It was also
shown that HSP90 can stabilize proteins in
inactive/active metastable conformation in the absence of
particular stimuli for example binding partners or small
molecule ligands. To the most important client proteins
belongs: oncogenic kinases like BRAF and v-SRC,
myosin heavy chain, telomerase reverse transcriptase and
ligand binding domain of steroid receptors. Blocking of
HSP90 activity in the cell is one of the most promising
approach to inhibits tumor growth and several small
molecule inhibitors are currently in the clinical studies.
HSP90 protein consists of three domains: N-terminal
ATPase domain, middle substrate binding domain and
C-terminal domain that is responsible for the
dimerization [1]. All three domains of the HSP90 protein
participates in protein-protein interactions. From
structural studies it's known that upon binding to the ATP
molecule HSP90 change conformation from open (with
non-interacting N-terminal domains) to the closed
conformation (with additional dimerization of the
N-terminal domains) [2]. In solution HSP90 protein
exists in the equilibrium between open and closed
conformation.
Several proteins, called co-chaperons, binds to
HSP90 protein and modulates its function by either
inhibiting its ATPase activity: like p23 and HOP protein
or by activating its enzymatic activity like AHA1 protein.
Other proteins are responsible for recruiting special class
of client proteins: for example Cdc37 protein is required
for the recruiting of kinases to the HSP90 complex. In
addition some of those proteins stabilizes one of the
conformations of HSP90 protein. For example p23
protein stabilizes closed conformation of HSP90 in the
complex with ATP.
Acknowledgments: This work was supported by the grant
(2012/05/N/ST3/03087) from National Science Center.
___________________________________________________
[1] M. Taipale, D. F. Jarosz, S. Lindquist Nat Rev Mol Cell
Biol 11 (2010) 515.
[2] K. A. Krukenberg, T. O. Street, L. A. Lavery,
D. A. Agard. Q Rev Biophys 44 (2011) 229.
[3] Y. Kadota, K. Shirasu Biochim Biophys Acta 23 (2012)
689.
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-10
determination how flow rate of sample flowing in a chip
can influence the morphology of amyloid aggregates or
rapid profiling of specific proteins in bodily fluids. Some
groups used microfluidics to mimic in vivo-like
conditions, by testing the effect of confinement and flow
on AA, but very few studied how long circulation in a
chip – similar to this taking place in blood vessels – can
itself influence amyloidogenesis.
Here we mounted a microfluidic system to study the
effect of long circulation on AA. We chose hen egg
white lysozyme (HEWL) to study these phenomena.
HEWL is a well-studied model protein, amyloid-prone,
comprising 129 amino acids, taking part in bacteria lysis.
It is an alpha helix-rich protein. We also used gemini
surfactants in our study to seek substances effectively
influencing AA. Gemini surfactants’ molecules consist of
two polar heads with attached hydrophobic tails and a
linker between the heads. They exhibit quite unusual
properties as in comparison to their conventional
(monomeric) surfactants they have higher surface
activity, better solubility or lower critical micellization
concentration and are a promising group of surfactants.
The microfluidic system used in our research is not
commonly used; microfluidic chips are rather utilised as
mixing, droplet forming or single flow stages. The main
goal of our research is to contribute to understanding of
AA mechanism by revealing the role of shear forces
occurring in microfluidic flow on AA.
The results of measurements carried out in this
project, including SAXS data, will be presented on the
conference.
Wed. 02. 09., 1240-1300
Influence of microfluidic flow on amyloid
aggregation of hen egg white lysozyme
W. Gospodarczyk*, M. Kozak
Department of Macromolecular Physics, Faculty of Physics,
Adam Mickiewicz University, Poznań, Poland
Keywords: amyloid aggregation, microfluidics
*e-mail: [email protected]
Amyloid aggregation (AA) is a specific type of
protein aggregation responsible for numerous serious
human diseases, such as Alzheimer disease, Parkinson
disease, type II diabetes, liver cirrhosis. Despite a vast
number of scientific groups has been attempting to
understand processes underlying AA, the exact molecular
mechanism has still not been deciphered. This
knowledge on AA would make seeking for therapeutic
solutions much more efficient. As many different
amyloid-prone proteins misfold in a similar way, there is
a chance of finding one medicine for a few different
diseases. AA research is not only focused on dealing
with AA mechanism, but also on a quest for substances
that could hamper AA aggregation, as there is a hope of
finding a medicine among them.
There has been an increased interest in using
microfluidics – a branch of technology and science that
makes use of microchips – devices enabling flow of
samples in channels of small cross-sections – in studying
amyloidogenesis process. Microfluidics helped to
overcome limitations of or enhance potential of
traditional, 'bulk' methods. For example, there have been
reported: ability to detect single nucleation sites of
amyloidogenesis and trace its propagation in time,
Acknowledgments: This work was supported by a research
grant (DEC-2013/09/N/ST5/02444) from National Science
Centre (Poland).
___________________________________________________
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KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
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eration with PREVAC) but instead of primary polycapillary optics we applied single bounce metallic capillaries
optics, designed and manufactured in our Laboratory.
The vacuum chumber is currently under construction and
is expected to be fully operational in September this year.
Single bounce gold capillaries with elliptic internal
shape have recently been redesigned and developed in
our Laboratory. Surface roughness was reduced up to
0.5 nm and slope error to 0.3 mrad. For these capillaries
an expected depth resolution varies from 3 µm (1 keV)
and 10 µm for 9 keV (Cu-Kα).
The spectrometer equipped with gold capillaries offers the possibility of elemental analysis with better
depth resolution than is offerred by glass polycapillaries
at energies below 9 keV.
To further extend analytical capabilities of single
bounce metallic capillaries, we will present a design of a
micro-XRF spectrometer using synchrotron radiation
(SR). Capillaries with parabolic shape will be applied in
order to focus SR. This proposal can be considered as a
part of our Polish Synchrotron SOLARIS.
Furthermore, we will compare the capabilities and
limitations of this spectrometer with others, that use
laboratory and/or synchrotron sources.
Thu. 03. 09., 1020-1040
Micro-X-Ray fluorescence spectrometer with
X-ray single bounce metallic capillary optics
for light element analysis
R. Mroczka1*, A. Sykuła1, E. A.Stefaniak1,2
1 Laboratory
of X-ray Optics, Centre for Interdisciplinary
Research, The John Paul II Catholic University of Lublin,
Konstantynów 1, 20-708 Lublin, Poland,
2 Department of Chemistry, The John Paul II Catholic
University of Lublin, Konstantynów 1, 20-708 Lublin, Poland,
Keywords: micro-XRF spectrometer, X-ray metallic capillary
optics, light elements analysis
*e-mail: [email protected]
In the last 20 years, due to the rapid development of
X-ray optics, micro X-ray fluorescence spectrometry
(micro-XRF) has become a powerful tool to determine
the spatial distribution of major, minor, and trace elements within a sample.
Micro-X-ray fluorescence (micro-XRF) spectrometers for light element analysis (6 ≤ Z ≤ 14) using glass
polycapillary optics are usually designed and applied to
confocal geometry. Two such X-ray optics systems are
used in this setup. The first one focuses the primary beam
on the sample; the second restricts the field of view of
the detector. In order to be able to analyze a wider range
of elements especialy with (6 ≤ Z ≤ 14), both sample and
detector are under vacuum. Depth resolution varies between 100 μm at 1 keV fluorescence energy (Na-Kα) and
30 μm for 17.5 keV (Mo-Kα) [1,2].
In order to improve resolution at energies below
9 keV, our group designed similar spectrometer (in coop-
Acknowledgments: This work was supported and co-funded
by the European Union as part of the Operational Programme
Development of Eastern Poland for 2007–2013, Priority I
Innovative Economy, Measure I.3. Support for Innovations and
The National Centre for Research and Development, Project no.
TANGO1,267102/NCBR/2015.
________________________________________________
[1] S. Smolek, B.Pemmer, M. Folser, C. Streli,
P. Wobrauschek, Review of Scientific Instruments 83
(2012) 083703.
[2] S. Smolek , T. Nakazawa, A. Tabe, K. Nakano, K. Tsuji,
C. Streli , P. Wobrauschek, X-ray Spectrometry 43 (2014)
93.
32
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
O-12
Thu. 03. 09., 1640-1700
S-01
Tue. 01. 09., 1640-1700
Solaris control and IT systems towards beamline
users
New developments in small spot and imaging
Near Ambient Pressure XPS
P. Goryl1*, C. J. Bocchetta1, Ł. Dudek1, P. Gałuszka1,
W. Kitka1, P. Kurdziel1, M. Ostoja-Gajewski1,
R. Różańska2, M. J. Stankiewicz1,
K. Szamota-Leandersson1, J. Szota1, T. Szepieniec2,
T. Szymocha2, A. I. Wawrzyniak1, K. Wawrzyniak1,
M. Zając1, Ł. Żytniak1
A. Thissen*, S. Bahr, T. Kampen, O. Schaff
SPECS Surface Nano Analysis GmbH, Voltastrasse 5, 13355
Berlin, Germany
*e-mail: [email protected]
Over the last 15 years, Near Ambient Pressure (NAP)
XPS has demonstrated its promising potential in a wide
variety of applications. Starting from the Catalysis and
Ice paradigm, the focus has shifted towards solid-liquid
interfaces, liquid jets and in-situ electrochemistry.
Initially, the experiments had to be carried out using
advanced synchrotron sources to reach reasonable count
rates. This is still state-of-the-art for most sensitive
analyses under NAP conditions. The windowless beam
entrance stages, that have been developed by SPECS
over the last years utilize all capabilities of modern
synchrotron beamlines for NAP-XPS. Furthermore,
SPECS PHOIBOS 150 NAP offers optimized
transmission for electrons, even at pressures up to and
above 100mbar, so researchers can now use it with
conventional X-ray and UV sources in their own
laboratories, as well. Because of the widened application
fields, standard XPS is now also attainable when
combined with easily adjustable monochromated X-ray
sources that offer stable operation, small excitations
spots, and high photon flux densities, even in Near
Ambient Pressure conditions. The latest designs and
results are presented showing small spot performance
for spot sizes < 30 µm, while also showcasing the latest
implementations of imaging NAP-XPS that uses a new
concept allowing for lateral resolved measurements
without a compromise in count rate and usability.
Highlighting on how sample environments (in situ cells
for gases and liquids, electrochemical cells, gas inlets)
and integration are both absolutely essential to obtain
relevant results from well-defined samples, the
presentation will demonstrate the use of NAP-XPS
systems for high throughput-XPS measurements, as well
as a variety of applications.
1
National Synchrtoron Radiation Centre SOLARIS,
Jagiellonian University, Czerwone Maki 98, 30-392 Krakow,
Poland
2 ACK Cyfronet AGH, Nawojki 11, 30-950 Kraków 23, Poland
Keywords: synchrotron radiation, tango, control system
*e-mail: [email protected]
The National Synchrotron Radiation Centre Solaris
has been built in Krakow and is now in commissioning
stage. Number of control and IT services has been
already provided. These allow for commissioning and
operation of the accelerator and both beamlines. In
parallel to commissioning there is ongoing development
of new services to facilitate convenient operation and
usage of the systems for synchrotron light users.
Tango CS control system, well established at
European synchrotron laboratories, has been deployed
and all controlled devices and systems has been
integrated. There are three separate instances of the
Tango running at Solaris. One serves accelerator and two
other serve two beamlines. Several high level application
has been prepared. Graphical user interfaces for
beamlines are mostly prepared with usage of Sardana
package and Taurus libraries At current stage end
stations are provided with vendor software and are not
yet integrated into the common Tango systems.
However, the integration is planned for near future.
Already operational network infrastructure will be
soon enhanced to provide full 10 Gb/s uplinks to enable
smooth data treatment for experiments producing large
amount of data. It is planned to allow direct export of
experiment results from an experimental station to the
PL-Grid infrastructure. This will give users possibility to
process data on the clusters using large number of tools
provided there.
A Digital User Office, which is important from the
user perspective, is being prepared in collaboration with
ACK Cyfronet AGH. It will be a point of access for
scientists looking for experiments opportunities and
letting them send and manage applications for beam
time.
The current status of the control and IT systems with
repsect to beamlines will be presented as well as plan for
future services.
___________________________________________________
Acknowledgments: Work supported by the European Regional
Development Fund within the frame of the Innovative
Economy Operational Program:
POIG.02.01.00-12-213/09
___________________________________________________
33
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
P-01
P-02
Synchrotron radiation photoemission study of
doped semiconductors valence band
The limit of CdTe solubility in PbTe and the
phase diagram of (Pb,Cd)Te solid solution
B.A. Orlowski*, E. Guziewicz, B.J. Kowalski, A. Reszka
R. Minikayev 1*, E. Dynowska1, A. Szczerbakow1,
A. M. T. Bell2, W. Szuszkiewicz1
Institute of Physics, Polish Academy of Sciences, Al. Lotnikow
32/46, 02-668 Warsaw,Poland
Institute of Physics, Polish Academy of Sciences, Al. Lotników
32/46, PL-02668 Warsaw, Poland
2 HASYLAB at DESY, Notkestr. 85 , D- 22607 Hamburg,
Germany
1
Keywords: synchrotron radiation, resonant photoemission,
Fano resonance
*e-mail: [email protected]
Keywords: synchrotron radiation, structure refinement, high
temperature, phase diagram
The synchrotron radiation as a strong continuous
radiation spectrum source in the wide photon energy
range (from infrared, through visible light, ultraviolet,
and up to the hard X-rays) was used to induce the Fano
type resonant photoemission [1,2] spectra.
The 4f electrons shell contribution to the valence
bands of selected semiconductors doped by rare earth
atoms were studied The impurity atoms were introduced
to the crystal during technology process or sequentially
deposited on the crystal clean surface. The sets of
photoemission spectra were acquired for the photon
energy range corresponding to 4d-4f Fano resonance.
The data were collected after each sequential treatment of
the sample. Measured spectra showed the contribution of
the 4f electrons as an additional peaks of density of states
in the valence band corresponding to rare earth 2+ and
3+ ions.
The presented results concern the change of the
semiconductor valence band density of states caused due
to contribution of 4f electrons states to the semiconductor
valence band structure. It results in a new distribution of
the valence band density of electronic states in
semiconducting
crystals,
nanoelements
and
nanostructures. The interaction of electrons creating the
structure of the valence band of a semiconducting
material with the open-shell electrons of rare earth
impurities strongly influences magnetic properties of
systems with reduced dimensionality (like quantum dots
or nanowires). Therefore revealing the contribution of
such impurity states to the region of the valence band has
become one of the important research problems in
electronic band structure studies.
The results allowed to determine the rich structure of
contribution of the 4f electrons to the valence band of the
semiconductor crystals and to distinguish the
contributions of 2+ and 3+ valence of it. The temperature
annealing leds to the change of their valence in
accordance with the value expected for the cation of the
host lattice of semiconductor. The binding energies and
the relative intensity of the correlated peaks were
determined.
*e-mail: [email protected]
In search of new materials for developing of the midIR optoelectronic or the thermo-electric devices based on
quantum dots an interesting system Pb1-xCdxTe solid
solution attracted a lot of attention. Extremely low
mutual solubility of both materials [1] results from the
difference in their crystal structure – rock salt (RS) for
PbTe and zinc-blende (ZB) for CdTe. The objects of
present investigation are unique bulk, single Pb1-xCdxTe
crystals (with x ≤ 0.11) [2], which were obtained at the
Institute of Physics of the Polish Academy of Sciences in
Warsaw by SSVG method [3]. The goal of the present
work was to study the structure properties and material
stability of Pb1-xCdxTe solid solution at high temperatures
and to get also new information on the temperature
dependence of lattice parameters, and CdTe solubility
limit in PbTe semiconductor compound.
In
situ
high-temperature
X-ray
diffraction
measurements were performed at the B2 beamline
(Hasylab/DESY) [4], using the Debye–Scherrer
geometry. The samples were prepared as a mixture of
powdered Pb1-xCdxTe crystals and fine diamond powder
(in the capacity of an internal standard [5]), and placed in
a thin-wall quartz capillary, rotating inside a graphite
heater during measurements. The Rietveld-method [6]
was used for the structural analysis.
The experimental data [7-11] published previously in
literature are mainly based on the results of DTA
measurements performed on Pb1-xCdxTe solid solution
with much worse crystal quality than that of present
samples. The present results did not confirm the
solubility limit known from the literature and suggested
the necessity of some correction of the relevant phase
diagram. The selected information on the Pb1-xCdxTe
solid solution, such as a part of the phase diagram and
CdTe solubility limit in PbTe for x ≤ 0.11 up to
T ≤ 1100 K will be shown and discussed.
Acknowledgments: This work was supported by the research
grant UMO-2014/13/B/ST3/04393 from National Science
Centre (Poland).
___________________________________________________
Acknowledgements: The work was supported by the Polish
National Centre for Research and Development (NCBiR)
through the project DZP/PBSII/1699/2013.
___________________________________________________
[1]
[2]
[1]
B.A. Orlowski „Spektroskopia fotoemisyjna rezonansowa typu
Fano” Monography: „Promieniowanie synchrotronowe
w spektroskopii i badaniach strukturalnych” editors:
B.J. Kowalski, W. Paszkowicz, E.A. Gorlich. 2011, in PTPS.
E. Guziewicz et al., Appl. Surf. Science 82 (2013) 326.
[2]
34
T. Schwarzl, E. Kaufmann, G. Springholz, K. Koike, T. Hotei,
M. Yano, W. Heiss, Phys. Rev. B 78(2008) 165320.
M. Szot, A. Szczerbakow, K. Dybko, L. Kowalczyk, E. Smajek,
V. Domukhovski, E. Łusakowska, P. Dziawa, A,. Mycielski,
T. Story, M. Bukała, M. Galicka, P. Sankowski, R. Buczko,
P. Kacman, Acta Phys. Pol. A 116 (2009) 959.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
[3] A. Szczerbakow, K. Durose, Prog. Cryst. Growth
Character. Mater. 51 (2005) 81.
[4] M. Knapp, C. Baehtz, H. Ehrenberg, H. Fuess, J. Synchr.
Radiation 11 (2004) 328.
[5] W. Paszkowicz, M. Knapp, C. Bähtz, R. Minikayev,
[6] P. Piszora, J. Z. Jiang, R. Bacewicz, J. AlloysCompd. 382
(2004) 107.
[7] J. Rodriguez-Carvajal, Newslett. IUCr Commission
Powd. Diffr. 26 (2001) 12.
[8] A. J. Rosenberg, R. Grierson, J. C. Woolley, P. Nocolik,
Trans. Met. Soc. AIME, 230 (1964) 342.
[9] V. Leute, R. Schmidt, Z. Phys. Chem. 172 (1991) 81
[10] N. Kh. Abrikosov, Semiconducting II-VI, IV-VI, and V-VI
Compounds, Plenum Press, New York (1969).
[11] H. Rutenberg, thesis, Münster (1985).
[12] Y. Liu, L. Zhang, D. Yu, J. Electron. Mater. 38 (2009)
2033.
35
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
(silicon substrate) and mono-crystalline (mica substrate)
structure.
Further studies were carried out in-situ. The structure of
the obtained films were studied immediately after the
synthesis process by reflection high-energy electron
diffraction (RHEED) and low-energy electron diffraction
(LEED). These techniques revealed the hexagonal
structure of surfaces.
The analysis of electronic structure was carried out
by X-ray photoelectron spectroscopy (XPS), it revealed
no additional elements such as oxygen, carbon and other
contaminants, even after several days of storage samples
in a vacuum chamber. The analysis of the chemical state
based on Bi 4f and Te 3d lines was in the agreement with
the literature data for this compounds. In the case of
polycrystalline samples the electronic structure was
tested for different stoichiometries (tellurium-rich layer,
the correct stoichiometry Bi2Te3 and sample depleted in
tellurium). For monocrystalline films the chemical states
of tellurium and bismuth were studied for two different
ways of growth process. In the first case sample growth
was realized in assumed correct flux ratio of bismuth to
tellurium (Bi/Te ratio 2/3). In the second one, the film
was deposited in the environment rich in tellurium.
Moreover, the XPS was used in order to specify the
termination of the Bi2Te3 films. The valence band
structure of the Bi2Te3 films was also investigated by
XPS and UPS techniques.
The topography of selected films was measured exsitu by atomic force microscopy AFM, thus the sample
was shortly (< 5 min) introduced to the external
atmosphere. The typical topography indicated the
Stranski-Krastanov like growth. The flat areas constitute
relatively small part of the total area of film surface. The
RMS was found to be of about 9.0(1) Å. The surface is
mostly formed by characteristic triangular-shaped islands
reflecting the hexagonal crystal structure in the [00l]
direction. A number of pyramidal-shape terraces with
1 nm high was detected which is in agreement with the
thickness of a single QL.
P-03
Atomic and electronic struture of Bi-Te films
grown at various conditions by MBE method
R. Rapacz1*, K. Balin2, M. Wojtyniak1, 2, J. Szade1
Chełkowski Institute of Physics, University of Silesia,
Uniwersytecka 4, 40-007 Katowice, Poland
1 Silesian Center for Education and Interdisciplinary Research,
75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
2 Institute of Materials Science, University of Silesia,
75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
1 August
Keywords: topological insulators, X-ray photoelectron
spectroscopy (XPS), molecular beam epitaxy MBE
*e-mail: [email protected]
Topological insulators (TI) are new remarkable
materials that have band gap in the bulk but can conduct
electricity on their surface via special surface electronic
states[1]. A unique feature of these states is the postulated
"topological protection" towards electrons scattering,
leading to high electrical conductivity. In addition, a
direct relationship between spin direction and the wave
vector of surfcae electrons results in a spin polarization
electric current. All of these remarkable properties of TI
make them the promising candidates for applications
ranging from spintronics to quantum computing.
One of the known TI’s is bismuth telluride Bi2Te3,
which for which the specific properties also retain in the
thin films form. The bulk component of the Bi2Te3
electronic structure is characterized by a narrow energy
band gap which has the value close to 0.16 eV (reported
in high quality undoped samples)[2]. The Fermi level
formed by the surface states is then placed roughly in the
middle of the bulk gap. Bi2Te3 crystallizes in the
rhombohedric structure belonging to the R3m space
group. The unit cell is built by quintuple layers (QL) – a
sequence of five atomic layers consisting of covalently
bonded Te(1)-Bi-Te(2)-Bi-Te(1). The QLs are weakly
bonded each-together by van der Waals interactions. The
thickness of the QL in Bi2Te3 is about 1 nm, while the
lattice constant extends for 3 QLs in the [001] direction.
Bi2Te3 layers were synthesized on the silicon (100)
and mica (001) substrate by molecular beam epitaxy
MBE in the co-deposition mode[3]. The growth process
was realized at the ultra-high vacuum conditions
(5∙10-9 mbar). The thicknesses of the deposited films
were from 10 to 30 nm. The layers had polycrystalline
Acknowledgements: The research was supported by the Forszt
project co-financed by EU from the European Social Fund.
___________________________________________________
[1] M. Z. Hasan, C. L. Kane, Rev. Mod. Phys., 82 (2015)
3045.
[2] K. Hoefer, C. Becker, D. Rata, J. Swanson, P. Thalmeier,
L. H. Tjeng, Proc. Natl. Acad. Sci. U.S.A. 111 (2014)
14979.
[3] R. Rapacz, K. Balin, A. Nowak, J. Szade, J. Cryst.
Growth 401 (2014) 567.
36
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
P-04
P-05
Compressibility and electronic structure
variation with pressure for EuVO4: A combined
experimental and computational study
Energy transfer processes to Eu3+ ions in
K5Li2GdF10 doped with Eu3+, Pr3+, Tb3+ and Dy3+
upon VUV excitation
W. Paszkowicz1*, J. López-Solano2,3, P. Piszora4,
B. Bojanowski5, A. Mujica2, A. Muñoz2, Y. Cerenius6,
S. Carlson6, H. Dąbkowska7
P. Solarz
Institute of Low Temperature and Structure Research, Polish
Academy of Sciences, ul. Okólna 2, 50-422 Wrocław, Poland
Institute of Physics PAS, al. Lotników 32/46, 02-668 Warsaw,
Poland,
2Departamento de Física Fundamental II, MALTA Consolider
Team, and Instituto de Materiales y Nanotecnología,
Universidad de La Laguna, Tenerife, 38205, Spain
3Izaña Atmospheric Research Center, Agencia Estatal de
Meteorología (AEMET), Tenerife, 38071, Spain
4 Faculty of Chemistry, A.Mickiewicz University, Umultowska
89b, 61-614 Poznań, Poland
5Institute of Physics, Szczecin University of Technology,
Aleja Piastów 48, 70-310 Szczecin, Poland
6 MAX IV Laboratory, Lund University, P.O. Box 118, SE-221
00 Lund, Sweden
7 Brockhouse Institute for Materials Research, McMaster
University, Hamilton, Ontario, L8S 4M1 Canada
1
Keywords: synchrotron radiation, energy transfer processes.
e-mail: [email protected]
The X-ray examination of small crystals of
K5Li2LnF10 (Ln = La−Gd) has proved that the materials
crystallize in a form of single phase. It is orthorhombic
16
(space group D2h
–Pnma), the unit-cell parameters are
a = 20:775 Å; b = 7:882 Å; c = 6:963 Å; for Ln = La.
The crystal structure is built from layers
perpendicular to the a axis, formed by LnF8 dodecahedra
and LiF4 tetrahedra. Rare-earth ions and lithium ions
occupy sites with CS symmetry, whereas potassium and
fluorine ions occupy sites with CS and C1 symmetry. The
crystal structure is uncommon in that the LnF8 polyhedra
do not share fluorine ions and the nearest rare-earth ions
are separated by more than 6.8 Å. Owing to these
features, exchange interactions between rare-earth ions
may be neglected and multipole interactions are expected
to be strongly reduced. Such a conditions allows to
analyze rather pure multipole interactions between ions.
Pr3+, Tb3+ and Dy3+ possesses metastable multiplets
situated in the blue area of the spectrum that should
transfer the energy to the low positioned Eu3+ 5D0 one
[1].
The Pr3+ ion can work as a sensitizer of Eu3+
luminescence from the 5D0. It has been discovered that
the Pr3+ ions to transfer an energy to the Eu3+ ions needs
the presence of Gd3+ ions. In K5Li2LaF10 system only a
luminescence of Pr3+ was observed upon excitation of f-d
bands of praseodymium [2]. It can suggest that excited
the Pr3+ ions very efficiently transfer the energy to Gd3+
ions. Such an efficient energy transfer has been observed
in other system YF3:Pr3+, Gd3+ [18]. At low temperature
emission spectra (not shown here) the Pr3+ f–f emission
upon UV–VUV excitation was observed. It suggests that
energy transfer from d levels of Pr3+ to Gd3+ states is
thermally dependent.
In the case of Dy3+ ions, no transfer upon excitation
into f-d bands of Dy3+ was observed to Gd3+ or Eu3+ ions.
Dysprosium is rather independent. As well as no transfer
from Dy3+ to other ions was not observed, no efficient
transfer to the 4F9/2 multiplet of Dy3+ was observed.
The best results was found for Tb3++Eu3+ system. It
occurs that upon excitation into f-d transitions bands of
Tb3+ an efficient luminescence from Eu3+ can be
observed in K5Li2GdF10 an K5Li2LaF10 matrixes. What is
more upon excitation of Tb3+ ions below the d levels no
efficient energy transfer from Tb to Eu was observed.
Such an observation is validated with analysis of the
decay curves of Tb3+ luminescence.
Keywords: high pressure, orthovanadate, equation of state,
energy gap
*e-mail: [email protected]
Europium orthovanadate, EuVO4, crystallizes in the
zircon-type structure (space group I41/amd, Z = 4) under
ambient conditions and is known to transform to a
scheelite-type structure at about 8 GPa. The equation of
state of this compound has already been studied.
However, the reported experimental and theoretical
values of the bulk modulus exhibit a considerable scatter,
for both, the zircon and schheelite-type polymorphs. As
for the dependence of the electronic structure with
pressure, such data have not been reported yet.
In the present study, structural, elastic and electronic
properties of zircon-type and scheelite-type europium
orthovanadate are investigated experimentally, by in-situ
X-ray diffraction using synchrotron radiation, and
theoretically within the framework of the density
functional theory (DFT). The obtained results on bulk
modulus show a perfect agreement of experiment with
theory. Discrepancies between the present values and
those earlier reported ones are attributed to differences in
the details of the experimental procedure. The calculated
band structure confirms that zircon-type europium
orthovanadate is a direct-gap semiconductor, with a
band-gap energy at zero pressure of 2.88 eV. The
variation of electronic structure and of the bandgap with
pressure is determined.
37
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
The 5D4 multiplet lifetime of 10 at% terbium doped
K5Li2GdF10 is 7500 s and is the same as in the Tb–Eu
system.
1.0
Luminescence intensity [a.u.]
0.9
0.8
Eu luminescence
Dy luminescence
Tb luminescence
0.7
Acknowledgments: This work was supported by
POIG.01.01.02-02-006/09 project co-funded by European
Regional Development Fund within the Innovative Economy
Program. Priority I, Activity 1.1. Sub-activity 1.1.2, which is
gratefully acknowledged. The research leading to these results
has received funding from the European Community’s Seventh
Framework Programme (FP7/2007-2013) under grant
agreement n° 226716, II-20090073 EC .
___________________________________________________
0.6
0.5
0.4
0.3
0.2
0.1
0.0
50
100
150
200
250
300
Wavelength [nm]
[1] G. H. Dieke, Spectra and Energy Levels of Rare Earth
Ions in Crystals, (H. M. Crosswhite and Hannah
Crosswhite Editors, Wiley Interscience, New York, 1968)
[2] P. Solarz, Optical Materials 31 (2008) 114.
[3] T. Hirai, H. Yoshida, S. Sakuragi, S. Hashimoto,
N. Ohno, Jpn. J. Appl. Phys. 46 (2007) 660.
Figure 1.. Excitations spectra of luminescence recorded at Eu
(red), Tb (blue), and Dy (blue) emission lines. The energy
transfer from the Tb3+ ions to the Eu3+ one can be observed in
the 150 – 275 nm region.
38
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
P-06
The compounds with samarium seem to be interesting
due to possible existence of mixed valence state of
samarium ions. As it was previously reported the free Sm
atom is divalent (4f6)(sd)2 while the trivalent (4f5)(sd)3
state is explained as the transfer of one 4f electrons to
the conduction band. The divalent state is stabilized at
the surface and the trivalent is essentially visible in bulk
samarium [7-10]. Some samarium compounds exhibit the
intermediate valence state and even similar like the pure
samarium the valence transition at the surface. The core
level splitting between Sm3+ and Sm2+ states is about
7.6eV. The separation of the final 4f multiplet structure
4f5 and 4f4 allow to distinct the two possible
configurations. In spite of using photoemission methods
sometimes it is difficult to point out weather Sm spectra
are a bulk or surface phenomena. However, one of the
best method which can be used to distinguish between
emission from the bulk or the surface samarium atoms is
the tilting samples from the normal direction. Sometimes
there is observed an increase of the intensity of
Sm3+(3d5/2) photoemission line with the decrease of the
takeoff angle [7].
Here we are focused on the influence of indium and
gadolinium substitution on the electronic structure of the
SmPdSn1-xInx (x=0.0, 0.5, 1.0) and GdxSm1-xPdIn (x=0.0,
0.5, 1.0) compounds. To the best of our knowledge the
electronic structure of studied compounds is reported
here for the first time. According to this investigation we
were able to deduce the valence state of samarium ions in
both systems.
Extended abstract
Electronic structure of selected ternary
samarium compounds
A. Bajorek1,2*, G. Chełkowska1,2
Institute of Physics, University of Silesia,
Uniwersytecka 4, 40-007 Katowice, Poland
2 Silesian Center for Education and Interdisciplinary Research,
University of Silesia, 75 Pułku Piechoty 1A, 41-500 Chorzów,
Poland
1A.Chełkowski
Keywords: rare earth alloys and compounds, photoemission
spectroscopy
*e-mail: [email protected]
Introduction
The ternary RPdSn or RPdIn compounds have been
intensively investigated in the past with respect to their
crystal structure, magnetic and transport properties [1-5].
Most of them are ruled by f-d interactions. However, in
compounds with hexagonal type of crystal structure some
properties are connected with the frustration in R
sublattice. Such interesting mechanism leads to the
possible existence of the mixed valence, heavy fermion
or Kondo effect.
The first group of compounds RPdSn where
R=Ce-Dy crystallize in the orthorhombic TiNiSi type of
crystal structure (Pnma space group) whereas with
R=Er-Sc crystallize in the hexagonal Fe2P structure
(P-62m space group). The compound HoPdSn can exist
in both structures and it depends on heat treatment of the
sample [1,3]. The second group of compounds RPdIn
(R=La-Sm,Y, Gd-Lu) with 4d elements crystallize in the
ZrNiAl - type hexagonal structure (P-62m space group)
[2,4,5].
The susceptibility of the policrystalline SmPdSn
compound deviates form Curie - Weiss behavior. As it
was previously reported this compound exhibits
antiferromagnetic ordering with TN about 12K. However,
in low temperature range there was noticed one more
peak which is probably connected with complex
magnetic structure [1,3,6].
The GdPdIn compound exhibits ferromagnetic phase
transition at TC=102K and Curie – Weiss behaviour with
the paramagnetic Curie temperature p=96.5K [2]
whereas the SmPdIn single crystal is a ferromagnet
below 54K and 0.21B/Sm along the easy magnetization
a – axis [4]. In mixed compounds SmPdSn1-xInx and
GdxSm1-xPdIn the ordering temperatures are lower than
80K [6]. Additionally, the M(H) magnetization curves for
SmPdSn and SmPdSn0.5In0.5 are not saturated [6]. It may
be connected with the complex magnetic structure. For
GdxSm1-xPdIn studied compounds M(H) is almost
saturated at 7T. The value of MS equals 0.21B/f.u,
3.36B/f.u and 7.52B/f.u for x=0.0, x=0.5 and x=1.0,
respectively. The estimated value of magnetocalotric
effect (MCE) is rather low and only for compounds
which contain Gd is close to 1 [J/kgK] at the applied
magnetic filed of 1T [6].
Experimental details
The polycrystalline samples SmPdSn1-xInx (x=0.0,
0.5, 1.0) and GdxSm1-xPdIn (x=0.0, 0.5, 1.0) were
prepared by arc-melting from high purity elements under
argon atmosphere. The melted samples were then
wrapped in tantalum foil, placed in quartz tubes and
annealed at 850C for one week. After annealing all
studied samples were single phase and their crystal
structure was checked by means of X-ray diffraction
(XRD) using Siemens D5000 diffractometer. The XPS
measurements were performed with the use of PHI
5700/660 Physical Electronics spectrometer. The spectra
were
analyzed
at
room
temperature
using
monochromatized Al K radiation (1486.6eV). The
surfaces of the samples were mechanically cleaned by
scrapping with a diamond file or cleaving in the
preparation chamber under high vacuum of 10-10 Torr.
After cleaning the samples were immediately moved into
the main chamber. This procedure was repeated until the
intensity of C1s and O1s photoemission lines was to
neglect or do not change in further cleaning of the
surfaces of the samples. All XPS measurements were
performed in vacuum of 10-10 Torr.
Results and discussion
Fig.1a displays the valence band (VB) spectra in the
broad energy range with core levels In4d and Sn4d. Each
VB spectrum was normalized with respect to the Pd4d.
The spin – orbit (L-S) splitting between 4d5/2 and 4d3/2
indium states is about 0.85eV and between tin states
39
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
about 0.9eV. This band does not change an energy shift
and forms maximum located at about 3.8eV below the
Fermi level (EF). The Gd4f level for compounds
containing gadolinium is shifted in comparison to pure
Gd (8eV). For GdPdIn this level is located at about
8.7eV and for Gd0.5Sm0.5PdIn at about 8.9eV below EF.
This energy shift can be connected with the change of
surroundings of Gd atoms The cusp visible in VB at
about 5.7eV is typical for trivalent Sm3+(4f) states which
give the contribution to VB below 5eV. The divalent Sm
states should be visible above 5eV. The intensity of
states at the Fermi level N(EF) is the highest for SmPdSn
and the lowest for GdPdIn (Fig.1b). It could be
connected with the contribution of Sn5p and Sm2+(4f)
which are located below 5eV. One can notice that N(EF)
is the highest for the compound which exhibits the lowest
magnetization.
compounds one of these peaks at about 1084eV is
enhanced by In M5N45N45 Auger line.
Similar
behaviour is observed for divalent samarium line
Sm2+(3d5/2) located at about 1073.3eV. One of its
components is enhanced by In M4N45N45 Auger line
(1076 eV). Therefore is difficult to estimate the 3+/2+
intensity ratio r, the coupling parameter  and the
occupation number of f shell nf by fitting 3d spectra
using Gunnarson–Schönhammer model [12]. The
separation between divalent and trivalent samarium
peaks equals about 8.5eV.
Figure 2. XPS photoemission core level spectra of the (a) Sm3d
region; (b) Sm and Gd 4d region.
The 4d spectra are presented in Fig.2b. The overlap
between divalent and trivalent samarium states and much
more complicated multiplet structure of Sm4d than Sm3d
states make the first spectra less attractive for detailed
analysis. The observed Sm4d mulitiplet structure is
typical for Sm3+ states. However at about 123eV is
visible sharp peak which is typical for Sm2+ states. Some
part of divalent spectrum is hidden under the stronger
trivalent component.
Figure 1. (a) The VB spectra in broad energy range for all
studied compounds; (b) The VB near by the Fermi level (EF)
normalized to Pd4d states. Inset represents the intensity of
states just below EF.
Figure 3. XPS photoemission spectra of the samarium core
level (a) 3d; (b) measured by tilting the SmPdSn sample in
three chosen takeoff angles.
Fig.2a represents Sm 3d spectra taken at 45 takeoff
angle and normalized to the maximum. There are visible
several core level lines. The highest intensity of states is
observed for Sm3+ lines which are located at about
1081.8eV (3d5/2) and 1073.3eV (3d3/2) energy range.
Each line of Sm3+ is composed of several peaks
according to multiplets produced by ionization of
samarium trivalent state. However for In - rich
We have also performed measurements by tilting the
samples from the normal emission direction (45) in
order to enhance emission from the bulk (30) and
surface (60) states. We have not observed significant
change of the (3+)/(2+) intensity ratio with the change of
takeoff angle. Fig.3. represents an example of this kind
40
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
of performed measurements for the SmPdSn compound.
This behaviour can be related to the roughness of the
surface. Therefore we have performed all investigation
on the cleaved samples and scrapped by a diamond file.
The results in both cases were nearly similar. Therefore
we can conclude that the mixed valence state of
samarium ions observed in studied compounds is not
connected with the valence transition at the surface but
rather with comes from bulk states.
lence state of samarium ions in studied compounds
comes from bulk states and not from the valence
transition at the surface.
___________________________________________________
[1] D. T. Adroja, S. K. Malik, Phys. Rev. B 45 (1992) 779.
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4315.
Concluding remarks
From all measurements performed for the
SmPdSn1-xInx (x=0.0, 0.5, 1.0) and GdxSm1-xPdIn (x=0.0,
0.5, 1.0) compounds the following conclusions can be
drawn:
– The change of the valence band spectra near by the
Fermi level (EF) is visible. The intensity of states at
the Fermi level is the highest for the SmPdSn and
the lowest for GdPdIn compounds. It is connected
with the contribution of each elements to the valence band, some hybridization effects and f-d interactions.
– The samarium core level spectra exhibit the contribution of Sm3+ as well as Sm2+ states. The separation between divalent and trivalent Sm3d parts
equals about 8.5eV. These two kind of peaks do not
change with the tilting the samples during measurements. Therefore we claim that the mixed va-
41
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
single crystal substrates and irradiated with the Ga+ ions.
For each configuration the as-grown samples (reference)
and irradiated ones with 2 different doses were chosen.
The applied doses corresponded to the level for which
the out-of-plane magnetization of the sample reaches
local maxima. In case of the Pt/Co/Pt trilayers the light
irradiation fluences corresponded to appearance of the
out-of-plane magnetization state. The whole sample
surfaces were irradiated point by point with light to
achieve quazi-uniformly irradiated area.
P-07
Local structure around Co atoms in the ion and
light irradiated magnetic trilayers
A. Wolska1*, M.T. Klepka1, I. Sveklo2, A. Wawro1,
A. Bartnik3, P. Mazalski2, R. Sobierajski1, J. Fassbender4,
A. Maziewski2
1Institute
of Physics, Polish Academy of Sciences, Warsaw,
Poland
2University of Bialystok, Department of Physics, Poland
3Institute of Optoelectronics, Military Academy of Technology,
Warsaw, Poland
4Institute of Ion Beam Physics and Materials Research,
Dresden, Germany
1.2
Absorption (arb.u.)
1.0
Keywords: synchrotron radiation, XAFS, magnetic thin layers
*e-mail: [email protected]
Ultrathin film systems containing magnetic
component, e.g. Fe, Ni or Co with tunable magnetization
direction (in-plane and out-of-plane), sandwiched
between nonmagnetic metals, are of particular
importance for spintronics as well as for technology of
magneto-optical memory devices. The oscillatory
behavior of the magnetization orientation driven by Ga+
ion irradiation has been already observed in the Pt/Co/Pt
sandwiches. It is possible to change irreversibly magnetic
anisotropy to one of two out-of-plane magnetization
branches induced by Ga+ ion irradiation dose [1].
Moreover,
recent
investigations
showed
that
magnetization can also be affected by femtosecond light
pulses irradiation [2]. Magnetic states of the irradiated
spots depend on the intensity of the femtosecond laser
pulses (λ=800 nm). In case of low fluence the changes of
the magnetization and magnetic anisotropy are reversible
and may trigger a magnetization precession [3,4]. With
higher light intensities irreversible changes of the
structure are achieved [2]. In comparison with
conventional thermal annealing of the sample [5] the
ultrafast laser annealing provides possibility to localize
deposited energy near the surface regions while substrate
temperature is almost unchanged, which is important for
technological applications.
Presented studies were focused on the Au/Co/Pt and
Pt/Co/Au trilayers irradiated with the Ga+ ions and the
Pt/Co/Pt trilayers irradiated with light pulses. The X-ray
absorption fine structure (XAFS) experiment was
performed at the BM08 beamline in ESRF. Both regions
X-ray Absorption Near Edge Structure (XANES) and
Extended X-ray Absorption Fine Structure (EXAFS)
were investigated. The signal was registered in a
fluorescence mode at 77 K in a normal incidence
configuration. The measurements were carried out at the
Co K-edge for the as-grown reference and modified
samples in order to determine changes in the local atomic
structure around the Co atoms. The investigations were
performed for the series of the Pt/Co/Au and Au/Co/Pt
trilayers grown by the MBE method on the sapphire
0.8
0.6
Pt/Co/Au
reference
branch1
branch2
0.4
0.2
0.0
7700
7720
7740
7760
7780
7800
Energy (eV)
Figure 1. XANES spectra at the Co K-edge of the as-grown
sample and the samples irradiated with the Ga+ ions.
The analysis of the samples irradiated with Ga+ ions
showed that in both configurations, Pt/Co/Au and
Au/Co/Pt, the modifications of the atomic structure
around the Co atoms are similar. This kind of evolution
can be connected with the increased number of the Pt/Au
neighbors in the first coordination sphere of the Co
atoms. As an example, the XANES spectra for the
Pt/Co/Au structures before and after irradiation are
presented in Fig. 1. XANES spectra of the samples
irradiated with light correspond to the spectra of the
samples irradiated with the higher dose of the Ga+ ions.
The detailed XANES and EXAFS analysis revealed that
both irradiation methods have similar influence on the
local structure introducing Pt or Au atoms into the first
coordination sphere.
Acknowledgments: This work has been supported by the
Polish National Science Center (Grant No. DEC2012/06/M/ST3/00475) and by the EU FP7 EAgLE project
under the grant agreement REGPOT-CT-2013-316014. We
acknowledge the European Synchrotron Radiation Facility for
provision of synchrotron radiation facilities and we would like
to thank Dr. Angela Trapananti for assistance in using beamline
BM08.
___________________________________________________
[1]
[2]
[3]
[4]
[5]
42
A. Maziewski et al., Phys. Rev. B 85 (2012) 054427.
J. Kisielewski et al., J. Appl. Phys. 115 (2014) 053906.
M. van Kampen, Phys. Rev. Lett. 88 (2002) 227201.
J. Kisielewski et al., Phys. Rev. B 85 (2012) 184429.
M. Galeotti, Surf. Sci. 297 (1993) 202.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Various numbers of laser interaction pulses were used
to control the synthesis of the nanofibrous structures. The
preliminary analysis revealed that the nanostructures are
formed due to the aggregation of nanoparticles with
diameters varying between 30 and 90 nm. With
increasing number of irradiating pulses the nanoparticles
have a tendency to aggregate and merge into spheres.
P-08
Morphological and structural modifications
induced in ultrathin metallic films by
nanosecond pulses from EUV laser-plasma
source
D. Klinger¹, I. Jacyna¹*, J. B. Pełka¹, A. Reszka¹,
E. Łusakowska¹, A. Wawro¹, M. Jakubowski¹,
A. Bartnik2, R. Sobierajski¹
1Institute
of Physics, Polish Academy of Sciences,
02- 668 Al. Lotników 32/46, Warsaw.
2Institute of Optoelectronics, Military University of Technology,
ul. gen. S. Kaliskiego 2, 00-908 Warsaw,Poland
Keywords: extreme ultraviolet (EUV) pulses, laser-plasma
source, Au films, surface morphology, multishots
*e-mail:[email protected]
Laser-induced ablation from a solid target is known
as an alternative physical method for nanofabrication.
The most recent effort includes using plasmonic metal
nanoparticles to improve the efficiency of quantum dot
solar cells and thin film solar cells [1,2].
The main difference between nanofiber and other
nanostructures (nanowire, nanotube, and nanorod) in
solar cell application is the well-organized morphology
structure [3].
In the present study a various number (up to 1200) of
extreme ultraviolet (EUV) pulses have been used to
create nanostructures at thin gold film of 80-nm
thickness initially deposited onto a silicon (100) wafer
using MBE technique.
The source was a 10 Hz laser-plasma source based on
a double-stream gas puff target created in a vacuum
chamber synchronously with the pumping laser pulse.
The target is formed by pulsed injection of Kr, Xe or a
KrXe gas mixture into a hollow stream of helium. The
EUV radiation is focused using a grazing incidence goldplated ellipsoidal collector. Spectrum of the reflected
radiation consists of a narrow feature with intensity
maximum at 10–11 nm.
After irradiations, the samples were characterized by
means of the interference-polarized microscopy,
scanning electrical microscopy (SEM), atom force
microscopy (AFM) and synchrotron X-ray diffraction
(SXRD).
Figure 1. Exemplary results of surface modifications studies,
obtained for 80nm Au film deposited on silicon irradiated with
a single EUV pulse. 1) center: interference-polaizing microscopy image, 2) upper left: AFM map near the crater edge area,
3) bottom left: height profile along a line crossing the crater
edge, 4) upper right: SEM image of the crater, 5) bottom right:
X-Ray Fluorescence map (Au M-emission line) of the crater.
At higher number of pulses they form entangled
fibrous nanostructures. The basic mechanism of laser
synthesis of nanoparticles could be explained by the
accumation of the dense cloud of atoms around the laser
spot of the gold target during the ablation [4-6].
Acknowledgments: The research leading to these results has
received funding from the European Community's Seventh
Framework Programme (FP7/2007-2013) under grant
agreement no 226716 and the Polish National Science Center.,
Grant No. DEC-2011/03/B/ST3/02453.
___________________________________________________
[1]
[2]
[3]
[4]
[5]
[6]
43
Aren't et al., Nano Lett. 12 (2012) 4070.
Jiang et al., Sol Energy Mater Sol Cells 102 (2012) 44.
Mahmood et al., Nanoscale Res. Lett. 9 (2014) 255.
Manickam et al., Opt. Exp. 17 (2009) 13869.
Tan et al., Opt. Exp. 17 (2009) 1064.
Amirkianoosh et al., Nanoscale Res. Lett. 7 (2012) 518.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
have been studied by interference optical microscopy,
atomic force microscopy and scanning electron
microscopy. The irradiation’s induced structural changes
of the trilayer were characterized by means of TEM
analysis of sample’s cross-sections and X-ray standing
wave experiment with fluorescence detection. The
obtained morphological and structural modifications
were compared with the changes of magnetization.
Correlation between magnetic anisotropy and structure of
the Co-Pt interfaces were observed. Moreover correlation
of induced perpendicular magnetic anisotropy with the
morphological changes on the top surface in the
irradiated regions were found.
P-09
Investigation of morphological and structural
changes in ultrathin Pt/Co/Pt trilayers induced
by nanosecond pulses from EUV plasma source
I. Jacyna¹*, D. Klinger¹, J. B. Pełka¹, R. Sobierajski¹,
P. Dłuzewski¹, M. T. Klepka¹, E. Dynowska¹,
A. Wawro¹, A. Wolska1, M. Jakubowski¹, A. Bartnik2,
I. Sveklo3, Z. Kurant3, D.Eichert4, I. Makhotkin5,
S. Yakunin6, A. Maziewski3
¹Institute of Physics, Polish Academy of Sciences, 02- 668
Al. Lotników 32/46, Warsaw
2Institute of Optoelectronics, Military University of Technology,
ul. gen. S. Kaliskiego 2, 00-908 Warsaw, Poland
3Laboratory of Magnetism, Faculty of Physics, University of
Bialystok, K. Ciolkowskiego 1L, 15-245, Bialystok, Poland
4Elettra-Sincrotrone Trieste, S.S. 14 Km 163.5 in Area Science
Park, 34149 Basovizza, Trieste, Italy
5MESA+ Institute for Nanotechnology, University of Twente,
Netherlands
6NRC Kurchatov Institute, Moscow, Russia
Keywords: nanosecond pulse, laser-plasma source, EUV light,
ultrathin films, Pt/Co/Pt, structure modification
*e-mail:[email protected]
Ultrathin film systems containing a magnetic
element, e.g. Fe, Ni or Co, sandwiched between
nonmagnetic noble metals, with tunable magnetization
orientation (in-plane and out-of-plane) are of particular
importance for spintronics as well as for technology of
magneto-optical memory devices [1,2].
The perpendicular magnetic anisotropy (orientation
of magnetization easy axis perpendicular to the film
surface) is considered in the systems to be related mainly
to the structural details of magnetic film and interfaces.
In case of a Pt/Co/Pt trilayers irradiated by different
light sources [3,4] and ions [5,6], an out-of-plane to inplane magnetization reorientation phase transition
together with an intermixing and disordering at the Co–
Pt interfaces were observed.
The aim of this work is to study the detailed structural
properties of trilayer systems containing ultrathin (a few
nm) Co layer sandwiched between Pt films (of several
nm thickness each). The structure of the studied samples
was modified by irradiation with nanosecond EUV
pulses, characterized by a Gaussian-like spatial intensity
distribution, generated by a laser produced plasma
source. The irradiations have been carried out both in the
single shot and in multi shot modes, with various
irradiation fluencies.
Morphological changes, together with structural
modifications induced on the irradiated surface spots,
Figure 1. Correlation of the diameter of surface morphology
and magnetical remanescence modifications regions measured
at trilayer 250Pt/30Co/30Pt by means of interferencepolaryzing microscopy and Magneto-optic Kerr effect,
respectively.
Acknowledgments: This work was partially supported by the
Polish
National
Science
Center
(Grant
No.
2012/06/M/ST3/00475). The research leading to these results
has received funding from the European Community’s Seventh
Framework Programme (FP712007-2013) under grant
agreement n° 312284 (CALIPSO) and from the EU FP7
EAgLE project under the grant agreement REGPOT-CT-2013316014.
___________________________________________________
[1] N. W. E. McGee, M. T. Johnson, J. J. de Vries and J. Aan
de Stegge, Appl. Phys. 73 (1993) 3418.
[2] B. Heinrich, “Ultrathin Magnetic Structures”, Springer,
Berlin, 1994)
[3] J. Kisielewski et al., Journal of Applied Physics 115,
(2014) 053906.
[4] E. Dynowska, et. al., Structural investigation of ultrathin
Pt/Co/Pt trilayer films under EUV irradiation; ISSRNS
2014(http://synchrotron.org.pl/publ/biulet/vol13/082.pdf);
submitted to Rad. Phys. Chem.
[5] A. Maziewski, P. Mazalski, Z. Kurant, et al., Phys. Rev. B
85 (2012) 054427.
[6] M. Sakamaki, et. al., Phys. Rev. B 86 (2012) 024418.
44
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
thickness. This is the evidence of very sharp interfaces
inside the multilayer.
P-10
Structural properties of Fe/Pt multilayers before
and after ion beam irradiation
E. Dynowska1*, A. Marynowska1, L. T. Baczewski1,
J. Fassbender2, R. Böttger2
1Institute
of Physics Polish Academy of Sciences,
al. Lotników 32/46, 02-668 Warsaw, Poland
2 Helmholtz Zentrum Dresden-Rossendorf,
Bautzner Landstrasse 400, 01328 Dresden, Germany
Keywords: X ray diffraction, thin metallic multilayers,
molecular beam epitaxy
Figure 1. X-ray diffraction pattern in the vicinity of 222 Pt
reflection performed for the as grown sample.
*e-mail: [email protected]
FePt alloys are extremely promising candidates for
future high density recording media due to its high magnetic anisotropy up to 7×107 ergs/cm2 [1]. The reason for
such high magnetic anisotropy is attributed to the transformation of the disordered face-centered cubic (fcc)
FePt alloy to the ordered face-centered tetragonal (fct)
one. Typical method of obtaining fct FePt alloy is post
annealing of Fe/Pt multilayers. However, the high temperatures (up to 700 C), used in this method are not
compatible with magnetic media manufacturing techniques. The better method for intermixing of the Fe/Pt
system is ion beam irradiation which does not require
such high temperatures [2]. The intermixing of the Fe/Pt
system may result in the formation of several different
phases: disordered fcc FePt, ordered fct FePt, iron-rich
Fe3Pt and platinum-rich FePt3.
In this paper we report the results of structural
characterization of several Fe/Pt multilayer samples
Al2O3(0001)/Pt10nm/(Fe1nm/Pt1nm)15/Pt10nm before
and after Ne+ ion beam irradiation. All samples of
5×3,3 mm size were grown simultaneously in molecular
beam epitaxy system at room temperature in 10-10 Torr
vacuum. All pieces were irradiated with Ne+ ions of the
energy 25 keV but each with different dose (21015 –
1 1016 ions/cm2), respectively.
The crystal structure of all samples has been
examined by X-ray diffraction methods. The PANalitycal
Empyrean X-ray diffractometer with Cu K1 radiation,
equipped with the Johansson monochromator Ge(111) in
the incident beam and a linear semiconductor strip
detector has been used. The symmetrical and
asymmetrical X-ray diffraction patterns were performed.
The examples of X-ray symmetrical patterns from the
as grown and irradiated multilayer are shown in Figures
1 and 2. On the basis of the first diffraction pattern
(Fig.1) it can be concluded that the Pt layers as well as
the superlattice Fe/Pt grow in the [111] direction. The
peaks marked by -1, -2 and +1 are the satellite lines from
the superlattice – from their positions the thickness of the
Fe/Pt bilayer (superlattice period C) can be calculated.
The X-ray pattern of the as grown sample in the vicinity
of 111 Pt reflection (not shown here) shows also the
presence of thickness fringes originating from the
individual layers, as well as from the whole structure
Figure 2. X-ray diffraction pattern in the vicinity of 222 Pt
reflection – sample irradiated with 25 keV Ne+ ions of 21015
ions/cm2 dose.
As it is seen in Figure 2 even the smallest of the
applied doses of irradiation completely changed the
crystal structure of the multilayer – as a result two kinds
of disordered fcc FePt alloys (W1 and W2) with different
composition have been formed. The intermixing of the
Fe/Pt superlattice caused the creation of the alloy with
composition of about Pt0.50Fe0.50. The composition of this
alloy practically does not change with increasing dose.
The reason of the W1 alloy formation is the diffusion of
the Fe atoms to the platinum cover layer – the Fe content
in this alloy increases with the increasing dose from
Fe0.14Pt0.86 to Fe0.26Pt0.74. Peak marked as Pt is related to
Pt buffer layer and it’s position is the same as that for the
as grown sample. The quality of the thickness fringes
from this layer deteriorates with the increasing dose what
evidences substantial damaging of respective interfaces.
Acknowledgments:This work was partially supported by the
European Regional Development Fund within Innovative
Economy Operational Programme: POIG.02.02.00-00-020/09.
_______________________________________________
[1] V. R. Reddy, S. Kavita, S. Amirthapandian, A. Gupta,
B. K. Panigrahi, J. Phys. Condens. Matter.18, (2006)
6401.
[2] D. Ravelosona, C. Chapptert, V. Mathet, H. Bernas,
J.Appl. Phys. 87, (2000) 5771.
45
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
group attached at two different positions, C6 and C8, to
the rigid coumarin ring. The electrochemical method was
applied for the synthesis of the complexes.
P-11
XANES and EXAFS studies of bioactive metalloorganic complexes in solid and liquid state
a
M. T. Klepka1*, A. Wolska1, A. Drzewiecka-Antonik1,
P. Rejmak1, G. Aquilanti2
b
O
OH
CH3
CH3
H3C
1
Institute of Physics Polish Academy of Sciences, Warsaw,
Poland
2 Elettra - Sincrotrone Trieste, Italy
H3C
Keywords: coumarin, metal-organic ligand complexes,
XANES, EXAFS
O
O
HO
H3C
O
O
O
Figure 1. Molecular structure of ligands a - HL1 and b - HL2
*e-mail: [email protected]
XAFS measurements were performed at the beamline
I811 at MAX-lab in Lund, Sweden and XAFS beamline
at Elettra in Trieste, Italy. First samples in the form of
microcrystalline powder were investigated in Lund. After
that solutions of complexes in organic solvents (DMSO;
DMF) were measured in Trieste.
Methodology of the analysis included several steps.
First, the compounds were initially characterized by
Fourier transformed infrared spectroscopy (FTIR). Next,
EXAFS data were fitted in order to get information about
local atomic order. XANES spectra revealed that Cu in
complexes is mostly 2+. Then, obtained results were
used to find proper model with help of the density
functional theory (DFT). Finally full potential multiple
scattering XANES calculations were performed.
Results of structural analysis for compounds in the
form of microcrystalline powder enabled us to propose
mechanism of metal-organic ligand interaction. Some
differences were observed between powder form and
solutions of respective complexes. During the
presentation details will be discussed and compared with
results from biological activity tests.
Extended X-ray absorption fine structure (EXAFS)
and X-ray absorption near edge structure (XANES)
spectroscopies already demonstrated their usefulness in
studies of disordered systems. These techniques provide
information about local atomic neighborhood and
coordination polyhedra around metal cations regardless
of the state or crystallographic form of the investigated
material. It is especially important for structural studies
of compounds without long range order like copper(II)
complexes of coumarins.
The natural as well as synthetic coumarins, therein
hydroxycoumarins, exhibit a large spectrum of biological
activity. Such derivatives proved usefulness as anticoagulants [1], antibacterial agents [2], antifungal agents
[3], biological inhibitors [4], chemotherapeutics [5] and
as bio-analytical reagents [6]. It has been found out that
coordination of metal ions to therapeutic agents (such as
simple coumarins) can improve their efficacy and
accelerate bioactivity. In many cases such metal
complexes are more potent and less toxic comparing to
the parent drug. Therefore, among others, also
biologically active metal complexes of coumarin based
ligands are being widely investigated. Creaven et al. have
investigated the antimicrobial activity of a number of
coumarin complexes with silver(I), copper(II) and
manganese(II) ions. For example, the Cu(II) complexes
exhibit antifungal activity against a clinical strain of C.
albicans comparable to that of the commercially
available antifungal drugs, i.e. ketoconazole and
Amphotericin B [7].
Our studies presented here were focused on
comparison between solid and liquid state of two
bioactive hydroxycoumarin complexes. Our goal was to
try to simulate environment similar to one during
biological activity tests and human body. As solvents
DMSO – dimethyl sulfoxide and DMF –
dimethylformamide were used. Previously synthesized
copper(II) complexes of two hydroxyligands: HL1 and
HL2 (Figure 1) were used. These ligands have acetyl
Acknowledgments: Experimental research was funded from
the Polish National Science Centre (Grant No. UMO2012/07/D/ST5/02251), The synchrotron experiment was
partially supported by the Baltic Science Link project
coordinated by the Swedish Research Council, VR. This
research was supported in part by PL-Grid Infrastructure.
Financial support from the EU FP7 EAgLE project under the
grant agreement REGPOT-CT-2013-316014 is gratefully
acknowledged.
___________________________________________________
[1]
[2]
[3]
[4]
[5]
[6]
[7]
46
J. W. Suttie, Clin. Cardiol. 13 (VI) (1990) 16.
A. H. Bedair, et al., Il Farmaco 55 (2000) 708.
T. Patonay, et al., Pharmazie 39 (1984) 86.
C. Gnerre, et al., Med. Chem. 43 (2000) 4747.
D. A. Egan, et al., Cancer Lett. 118 (1997) 201.
M. Jime´nez, et al., J. Chrom. A 870 (2000) 473.
B. S. Creaven, et al., J. Inorg. Biochem. 103 (2009) 1196.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
agreement with the model. Therefore, the reference
material was not fully hydrated.
The EXAFS spectra of investigated materials at Zn
K-edge and their FT modules noticeably differed (Fig.
1). In the case of catalysts, the number of atoms in the
subsequence coordination spheres was smaller than in the
model of reference material. Finally, it was proved, that
the atomic order resembles rather a tetrahedral structure
with four N atoms around Zn (anhydrous phase) instead
of 6 in cubic structure (hydrated phase). Therefore, the
stoichiometry and structure change in catalysts after
introduction of ligands.
P-12
XAFS estimation of the catalytic centre in double
metal cyanide catalysts
K. Lawniczak-Jablonska1*, A. Chruściel2
1Institute
of Physics, Polish Academy of Sciences, Lotnikow Str
32/46, 02 668 Warsaw, Poland
2MEXEO, 47 225 Kędzierzyn-Koźle, Energetykow Str 9, Poland
Keywords: DMC catalysts, XAFS.
*e-mail: [email protected]
Double metal cyanide catalysts (DMC) are widely
exploited in industrial ring opening polymerization of the
epoxydes [1]. This group of catalysts is successfully
applied and continuously improved for few decades, but
the knowledge on the molecular nature of their
particularly high activity and selectivity is limited to
some phenomenological hypotheses. To shine some light
on the relation between structural and chemical
properties of DMC catalysts and their activity, XAS
studies were performed in cooperation with MEXEO
Kędzierzyn-Koźle Company. The DMC catalysts (MEODMC) and the reference material were synthesized by
MEXEO. The reference material was the hydrated trizinc
bis[hexacyanocobaltate(III)] compound (Zn3[Co(CN)6]2
·nH2O) of negligibly low catalytically activity without
practical application. Only after introduction to its
structure appropriate kinds of organic ligands, catalytic
activity increases. The synthesis started from
K3[Co(CN)6]2 and ZnCl2 raw materials. In the
investigated samples, the tert-butanol (tBuOH) or 1,2dimethoxyethane (glyme)) ligands were introduced in
catalyst preparation process. These ligands are the most
frequently used in commercial application of DMC
family of catalysts. The commercial DMC catalyst was
used as a comparative DMC catalyst.
All samples were in the form of powder. The
introduction of the ligands change the morphology of the
DMC material from cubic observed in reference material
to kind of irregular sheets with very extended surface.
The EXAFS analysis of the Zn and Co K-edges was
performed to exam the local atomic order around Zn and
Co atom in the reference material, the MEO-DMC
catalysts and the commercial catalyst. The XAS
measurements were performed at SOLEIL, France
(SAMBA station).
In agreement with the XRD results, the model for the
reference material was assumed to be a cubic structure
(Fm-3m) with water and a lattice constant of 1.0249 nm.
This model provides for the EXAFS analysis the starting
parameters including the number, kinds and distance of
atoms in the subsequence coordination shells in ideal
(Zn3[Co(CN)6]2·12H2O) reference material. The EXAFS
analysis of the Zn and Co K-edge indicated, that in the
considered reference material, instead of 24, only few
oxygen atoms were detected. Furthermore, the number of
other atoms in the coordination spheres was in the
Figure 1. The comparison of FT modules of the experimental
Zn K-edge spectra for investigated materials.
Several models of atomic order around Zn were
considered. The best fit to the EXAFS data was for the
model assuming that majority of Zn atoms in MEODMC catalyst still have the local atomic order as should
be in the reference anhydrous material with tetrahedral
structure but about 20% of them have Cl in the first
coordination sphere (Fig. 2).
Figure 2. Fit of the EXAFS data to the final model of the local
atomic structure around Zn atoms for MEO-DMC catalyst.
The local atomic structure around Co atom was
practically not changing for all investigated materials
(Fig. 3). Moreover, has the atomic order like in the
hydrated reference material (octahedral) with 6 C atoms
as near-neighbors. This confirmed that Co metallic centre
is not active during the catalyst preparation.
On the basis of performed analysis, the following
model of investigated DMC catalysts is proposed.
47
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Catalysts form cluster-like complexes with the Co
atomic structure not affected as compare to reference
hydrated (cubic) material.
clusters, Zn atoms are bounded partially with groups of
cyanide and with chlorine atoms from the ZnCl2 or
oxygen atoms from the ligand. The amount of Cl
detected by EXAFS in all investigated samples was in
agreement with that estimated by energy-dispersive
X-ray spectroscopy (EDS) and X-ray photoelectron
spectroscopy (XPS) measurements. This model explains
the fact that X-ray diffraction pattern for investigated
catalysts cannot be described by any of know phase. The
atomic order around majority of Zn atoms resembles
anhydrous phase, but that around Co hydrated phase. The
performed analysis of EXAFS provided direct
experimental evidence for the phenomenological
hypotheses postulated by Zhang et al., [2] and for
calculation performed by Wojdeł et al., [3].
___________________________________________________
[1] A. Chruściel, W. Hreczuch, J. Janik, K. Czaja,
K. Dziubek, Z. Flisak, A. Swinarew,: Ind. Eng. Chem.
Res. 53 (2014) 6636.
[2] X.-H. Zhang, Z.-J. Hua, Sh. Chen, F. Liu, X.-K. Sun,
G.-R. Qi, Appl. Catal. 325 (2007) 91.
[3] J. C. Wojdeł, S. T. Bromley, F. Illas, J. C. Jansen, J. Mol.
Model. 13 (2007) 751.
Figure 3. The comparison of FT modules of the experimental
Co K-edge spectra for investigated materials.
The Zn atoms inside the clusters have atomic order
like in anhydrous reference material (4 N atoms). This
explains this part of the Zn atoms in EXAFS analysis
which have an atomic order similar to that in the
reference anhydrous material. At the surface of the
48
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
counterparts. This study was performed on mixed system
composed of two types of trigemini surfactant and lipids
(DMPC, DOPE, DPPC). The ability to bind nucleic acids
was tested on three types of DNA varying in size i.e.
21 bp, 200 bp or 20 kbp.
To obtain structural information about formed
systems, small angle X-ray scatering (SAXS)
measurements using synchrotron radiation were
performed at Beam Line P12 (EMBL Outstation c/o
DESY Hamburg, Germany).Additionally, to characterize
conformational changes in thelipid structures and to
investigate the nature of phase transitions in solution,
infrared spectroscopy (FTIR) and differential scanning
calorimetry (DSC) were used. To get an insight into
process of complex formation with nucleic acid, circular
dichroism (CD) spectroscopy and electrophoretic
experiments were performed.
Results indicate that trigemini surfactants formed
stable complexes with DNA more efficiently than gemini
surfactants, (i.e. at lower concentrations in solution).
The addition of lipids also improves the efficiency
of the complexation.
P-13
Trimeric surfactants – new effective carries
for gene therapy
Ż. Kołodziejska*, Z. Pietralik, M. Kozak
Department of Macromolecular Physics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
Keywords: gene therapy, trimericsurfactants, lipoplex
*e-mail: [email protected]
One of the most important goal of modern medicine
is to develop biocompatible, effective, non-toxic and
synthetic systems to transport of therapeutic substances
into cells. The selection of the most suitable carrier can
provide successful treatment for both congenital
andacquired diseases. Due to the low toxicity,
biocompatibility, and simplicity of the manufacturing
process, complexes based on surfactants and lipids are
thought to have great potential as carriers, especially
for gene therapy, in which genetic material is
the therapetic substance [1, 2]. Such systems represent
a compromise between the biocompatibility provided by
natural lipid molecules and toxicity of surfactants, which
presence is necessary due to binding abilities that ensure
the effectiveness of complexation of nucleic acids [3, 4].
Our studies focus on trimeric (also known as
trigemini) surfactants as they are characterised by better
surface-activeproperties, than their dimeric or monomeric
Acknowledgments: This research project has been financed by
the funds from the National Science Centre (Poland) granted on
the basis of decision no. DEC-2011/01/B/ST5/00846.
___________________________________________________
[1] D. W. Emery, Clin. Appl. Immunol. Rev. 4 (2004) 411.
[2] D. Ibraheem, A. Elaissari, H. Fessi, Int. J. Pharm. 459
(2014) 70.
[3] R. Zana, Adv. Colloid Interface Sci. 97 (2002) 205.
[4] L. Karlsson, M. C. P. van Eijk, O. Söderman, J. Colloid
Interface Sci. 252 (2002) 290.
49
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
The influence of various concentrations of selected
surfactants on different structural forms of DNA (single
strand DNA, double strand DNA and RNA oligomers)
was investigated using circular dichroism (CD)
spectroscopy and gel electrophoresis.
The small angle scattering of synchrotron radiation
(SR-SAXS) studies were also performed on selected
lipoplexes based on short DNA and RNA double
stranded oligomers (21 bp), single strand DNA (23-mer)
and sugar-based surfactants. The SAXS data for
nanosystems studied were collected on P12 beam line of
EMBL Hamburg Outstation at PETRA III storage ring
(DESY).
A series of toxicity and transfection tests of these
lipoplexes were performed using HeLa and fibroblasts
(GM04033 and GM07492 line).
The results obtained revealed the unique properties of
such designed systems. Even small amounts of lactosebased surfactants, that bind strongly to DNA or RNA,
can cause a change of nucleic acid from one
conformation to another.
We can conclude, that sugar-based surfactants could
be useful as potential vectors for transfer genetic material
into mammalian cells during non-viral gene therapy.
Thanks to their construction these carriers can be able to
deliver the genes of various sizes to the cells, which is
difficult using viral gene delivery systems.
P-14
Structural studies of nanosystems based on
zwitterionic sugar-based surfactants as
innovative gene delivery systems
M. Skupin1*, Z. Pietralik1, K. Sobczak2, R. Zieliński3,
M. Kozak1
1Department
of Macromolecular Physics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
2Department of Gene Expression, Faculty of Biology, Adam
Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland
3Faculty of Commodity Science, University of Economics,
Al. Niepodległości 10, 60-967 Poznan´, Poland
Keywords: small angle X-ray scattering, gene therapy, sugarbased surfactants, cytotoxicity, circular dichroism
*e-mail: [email protected]
One of the most important advantages of synthetic
non-viral drug delivery systems is the improved
transfection efficiency [1]. Broad range of amphiphilic
dicationic surfactants, known as gemini surfactants, is
currently studied for gene delivery purposes [2].
Unfortunately the disadvantage of these systems is their
cytotoxicity.
The presented here studies indicated, that an effective
complexation between DNA or RNA and zwitterionic
sugar-based surfactants leads to the compaction of the
nucleic acids. This effect has potential applications for
preparation of gene delivery systems with reduced
toxicity and improved transfection efficiency. Such
systems can protect the genetic material against the
degeneration by intracellular nucleases and also can
promote the penetration of nucleic acid into the target
cell.
Acknowledgments: This research project has been financed
by the funds from the National Science Centre (Poland)
granted on the basis of decision no. DEC2011/01/B/ST5/00846.
___________________________________________________
[1] E. Cevher, A. Sezer, E. Çağlar, Recent Advances in Novel
Drug Carrier Systems, 2012.
[2] Z. Pietralik, R. Krzysztoń, W. Kida, W. Andrzejewska,
M. Kozak, Int J. Mol. Sci. 14 (2013) 7642.
50
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
In this work we present results of small angle X-ray
scattering (SH-SAXS), circular dichroism (CD), gel
electrophoresis studies and cellular tests of the
complexes formed between two tricationic surfactants:
1,2,3-propantriol [oxomethyl-3-(1-dodecylimidazolium)]
chloride
and
1,2,3-propantriol
[(oxomethyl)
dimethyldodecylammonium] chloride with short 21 bp
double stranded nucleic acid oligomers dsDNA and
siRNA [6-7].
First of all we conducted complexation process, than
characterized main structural parameters of the obtained
structures (like size, shape, spatial structure, resultant
charge, morphology), described conformational changes
of nucleic acids bound in them and finally we prepared
probable models of these complexes. Moreover we
performed also toxicity tests on HeLa and human
fibroblasts cell cultures using our systems to find out
their influence on these lines. All these results proved to
be very interesting.
P-15
Studies of dsDNA and siRNA oligomers in
complexes with tricationic surfactants using
biophysical methods
W. Andrzejewska*, M. Skupin, M. Kozak
Department of Macromolecular Physics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, Poznan, Poland
Keywords: gene therapy, dsDNA, siRNA, tricationic
surfactants, X-ray scattering, circular dichroism, gel
electrophoresis, cell cultures
*e-mail: [email protected]
Among the most intensively studied areas of the
science today we can find gene therapy – the innovative
and probably the most promising method for treatment of
all types of diseases so far incurable. The aim of gene
therapy is the induction of changes in the gene machinery
of diseased cells that cause blockage or destruction of
abnormal genes or contribute to the production of factors
acting antagonistically. This could be done by
introducing a short RNA molecules (transgenes) which
are able to act in this way. Unfortunately, in practice, it
creates a lot of problems, mostly in the introduction of
these nucleic acid to the cell without inducing
immunological response. The solution is to find a
suitable carriers, which could solve these problems[1-4].
Our research indicates that this potential have spatial
structures formed by self-organized quaternary
ammonium salts – surfactants [5]. In the range of new
amphiphilies, tricationic surfactants, featuring three
hydrophobic chains (hydrophobic moieties) and three
polar head groups linked by a spacer, seems to be quite
promising. Their physicochemical properties making
them able to create a stable, biocompatible complexes
with dsDNA and siRNA.
Acknowledgments: This research project has been financed by
the funds from the National Science Centre (Poland) granted on
the basis of decision no. DEC-2011/01/B/ST5/00846).
___________________________________________________
[1] R. Zieliński, Surfactants – structure, properties,
applications (in Polish), WUP (2009) Poznan.
[2] Ch. Wang, X. Li, D. Wettig, I. Badea, M. Foldvarid, M.E.
Verrall, Phys. Chem. Chem. Phys. 9 (2007) 1616.
[3] C. Amoruso, T. Lagache, D. Holcman, SIAM J. Appl.
Math. 71(6) (2011) 2334.
[4] B. Ma, S. Zhang, H. Jiang, B. Zhao, H. Lv, J. of Cont.
Rel. 123 (2007) 184.
[5] Z. Pietralik, R. Krzysztoń, W. Kida, W. Andrzejewska,
M. Kozak, Int. J. Mol. Sci. 14 (2014) 7642.
[6] J. Pernak, A. Skrzypczak, G. Lota, E. Frąckowiak, Chem.
Eur. J. 13 (2007) 3106.
[7] F. Mutelet, J. Ch. Moise, A. Skrzypczak, J. Chem. Eng.
Data 57 (2012) 918.
51
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
The first step to form the VLP is the characterization
of the virus capsid proteins by physical methods. CryoTEM study was conducted to determine the size and
morphology of the native capsid. Low resolution
structure and size distribution was confirmed by: Small
Angle X-ray Scattering (SAXS), Dynamic Light
Scattering (DLS) and Nuclear Magnetic Resonance
(NMR). Obtained scattering curves allowed us to create a
model of BMV shell. Typical for plant viruses
pH-depending closing of capsid pores was also studied.
This can be useful for packaging of nanoparticles into the
viral capsid. Attenuated Total Reflectance–Fourier
Transformed Infrared Spectroscopy (ATR-FTIR) and
Circular Dichroism (CD) techniques was also made to
examine changes in the secondary structure as a function
of pH of the solution.
One of the method of creation of VLP with
nanoparticles is dialysis of ions through the pores and
their reduction inside of the capsid. Formation of the
magnetite nanoparticles from iron ions within the BMV
capsid has been made and confirmed by DLS and Mass
Spectroscopy (MALDI-TOF) studies.
P-16
Physical characterization of BMV capsid protein
M. Kręcisz1*, J.D. Rybka1** S. Haracz1, A. Strugała1,2,
I.Zhukov3, A. Urbanowicz2, M. Figlerowicz2, M. Kozak4,
M.Giersig1,5
1 Faculty
of Chemistry, Wielkopolska Center for Advanced
Technologies, Adam Mickiewicz University, Umultowska 89C,
61-614 Poznan, Poland
2Institute of Bioorganic Chemistry, Polish Academy of Science,
Z. Noskowskiego 12/14, 61-704 Poznan, Poland
3Institute of Biochemistry and Biophysics, Polish Academy of
Sciences, Pawinskiego 5a, 02-106 Warszawa, Poland
4Faculty of Physics, Adam Mickiewicz University,
Umultowska 85, 61-614 Poznan
5Institut für Experimentalphysik, Freie Universität Berlin,
Arnimalle 14, 14195 Berlin, Germany
Keywords: synchrotron radiation, virus, dynamic light
scattering, transmission microscopy, secondary structure,
spectroscopy FTIR, circular dichroism, nmr
*e-mail: [email protected]
**e-mail: [email protected]
Acknowledgments: This work was supported by
UMO-2012/06/A/ST4/00373 grant from National Science
Centre (Poland)
___________________________________________________
Brome Mosaic Virus (BMV), an icosahedral RNA
plant virus, can be used to create nanocages and viruslike particles (VLP's). Virus capsids packed with
nanoparticles are also very promising tool for medical
applications. Particularly VLP with magnetite cores may
be useful in hyperthermic cancer therapy, Magnetic
Resonance Imaging (MRI) and processes connected with
sorting and recognition of cells.
[1] P. I. Haris, F. Severcan, J Mol Catal B-Enzym 7 (1999)
207.
[2] M. Casselyn, et al., Acta Cryst., D57 (2001) 1799.
[3] S. L. Calhoun, A. L. Rao, Arch Virol. 153 (2008) 231.
52
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
[2] and ethyl acetate [3], studied experimentally as well
as
theoretically.
The
high-resolution
VUV
photoabsorption spectra shown here were measured at
the UV1 beam line, using the ASTRID synchrotron
facility in Aarhus University, Denmark. The
photoelectron spectra of esters were measured either at
the VLS-PGM beamline at the Canadian Light Source
facility in Saskatoon, Canada, using a Double Toroidal
Coincidence Spectrometer or at the Université de Liège,
Belgium, using the He(I) radiation.
P-17
Valence and ionic lowest-lying electronic states
of small esters studied by high resolution
vacuum ultraviolet photoabsorption,
photoelectron spectroscopy and ab initio
calculations
M. A. Śmiałek1;2*, M. Łabuda3, J. Guthmuller3,
S. V. Hoffmann4, N. C. Jones4, M. A. MacDonald5,
L. Zuin5, M.-J. Hubin-Franskin6, J. Delwiche6,
D. Duflot7, N. J. Mason2, P. Limão-Vieira2,8
1Department
of Control and Power Engineering, Faculty of
Ocean Engineering and Ship Technology, Gdańsk University
of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk,
Poland
2Department of Physical Sciences, The Open University,
Walton Hall, Milton Keynes, MK7 6AA, United Kingdom
3Department of Theoretical Physic and Quantum Information,
Faculty of Applied Physics and Mathematics, Gdańsk
University of Technology, Gabriela Narutowicza 11/12, 80-233
Gdańsk, Poland
4
ISA, Department of Physics and Astronomy, Aarhus
University, DK 8000 Aarhus C, Denmark
5Canadian Light Source Inc., 44 Innovation Boulevard,
Saskatoon SK S7N 2V3, Canada
6Département de Chimie, Université de Liège, Institut de
Chimie-Bât. B6C, B-4000 Liège, Belgium
7Laboratoire de Physique des Lasers, Atomes et Molécules
(PhLAM), UMR CNRS 8523, Université Lille 1 Sciences et
Technologies, F-59655 Villeneuve d’ Ascq Cedex, France
8Laboratório de Colisões Atómicas e Moleculares, CEFITEC,
Departamento de Física, Faculdade de Ciências e Tecnologia,
Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
Figure 1. Photoelectron (upper) and photoabsorption (lower)
spectrum of isobutyl formate, C5H10O2.
Keywords: synchrotron radiation, photoelectron,
photoabsorption spectra, esters, ab initio calculations
The results presented here are supported by ab initio
calculations in order to allow for correct assignment of
all vertical and adiabatic ionization energies resolved in
the spectrum as well as proper assignment of valence
states and Rydberg transitions found in the
photoabsorption spectrum.
*e-mail: [email protected]
Esters are an important class of oxygenated volatile
organic compounds used in food flavorings, perfumes
and other cosmetic products. They are present in fruits
and pheromones and are emitted to the atmosphere
naturally. Esters are also formed in the atmosphere as a
product of the oxidation of ethers. Some of them form
poly-molecule chains and are used in plastics.
Phosphoesters form DNA backbone, while nitroesters are
known for their explosive character. Some small ester
molecules were reported to be found in the interstellar
space. It was also shown that esters may be a product of
hydroxyl radical-initiated oxidation of various ethers in
troposphere.
Although esters are not very toxic, their degradation
in the atmosphere may lead to production of more toxic
and reactive species.
In our present study we have focused on smaller
monoesters. The main purpose of our work is to
understand, how the carboxylic and alcohol group
distribution within the molecules influences their
physical properties and reactivity.
In this communication we would like to present our
findings for ethyl formate [1], isobutyl formate (Figure 1)
Acknowledgments: The authors wish to acknowledge the
beam time at the ISA synchrotron at Aarhus University,
Denmark, supported by the European Union (EU) I3
programme ELISA, Grant Agreement No. 226716. We also
acknowledge the financial support provided by the European
Commission through the Access to Research Infrastructure
action of the Improving Human Potential Programme. A part of
research described in this paper was performed at the Canadian
Light Source, which is supported by the Natural Sciences and
Engineering Research Council of Canada, the National
Research Council Canada, the Canadian Institutes of Health
Research, the Province of Saskatchewan, Western Economic
Diversification Canada, and the University of Saskatchewan.
All calculations have been performed at the Academic Center
(CI TASK) in Gdańsk and at Universitätsrechenzentrum of the
Friedrich-Schiller University in Jena.
___________________________________________________
[1] M. A. Śmiałek et al., J. Chem. Phys. 141 (2014) 104311.
[2] M. A. Śmiałek et al., J. Phys. Chem. A, submitted
[3] M. A. Śmiałek et al., in preparation
53
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
P-18
P-19
Hydrogen migration in formation of NH(A3Π)
radicals in photodissociations of isoxazole and
pyridine molecules
Spectroscopic characterization of human
cystatin C and its mutants
Z. Pietralik1*, A. Szymańska2, M. Kozak1
T. J. Wasowicz1*, A. Kivimaki2,3, M. Coreno3,4,
M. Zubek1
1Department
of MaclomolecularPhysics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
2Department of Medicinal Chemistry, Faculty of Chemistry,
University of Gdansk, Sobieskiego, Gdansk, Poland
Department of Physics of Electronic Phenomena, Gdańsk
University of Technology, ul. G. Narutowicza 11/12, 80-233
Gdańsk, Poland
2 CNR-IOM, Laboratorio TASC, 34149 Trieste, Italy
3Gas Phase [email protected], Basovizza Area Science Park,
34149, Trieste, Italy
4CNR-IMIP, Monterotondo, 00016 Roma, Italy
1
Keywords: Human Cystatin C, secondary structure, FTIR, CD
*e-mail: [email protected]
Human cystatin C (HCC) is a small β-protein
consisting of 120 amino acidsthat is found in all
nucleated cells. Physiologically, its function is to regulate
the catalytic activity of cysteine proteas. This protein is
also associated with two types of amyloid disorders. First
one is hereditarycystatine C amyloid angiopathy
(HCCAA), which is related to the L68Q mutation and it
is causing brianhemorrages [1]. The second disorder is
connected with deposition of amyloid β-fibrils where the
wild-type cystatin C is present as co-precipitant [2,3].
The aim of our studies was the spectroscopic
characterisation of the native and mutated forms of
human cystatin C in solution.Particullary mutants V57N,
V57P, V57G, V57D and L68Q were tested. The
secondary structure content in the broad range of
temperatures, in solution was evaluated on the basis of
Fourier transformed infrared spectroscopy (FTIR) and
circular dichroism spectroscopy (CD). Additionally the
overall fluerescence and dynamic light scattering (DLS)
was also recorded.
Fourier self–deconvolution procedure was used to
assign all the components of the Amid-I band to
particular secondary structures [4]. Obtained data was
compared with CD-based percentage content of
secondaty structures, for which spectra were recoreded in
temperature range from 5 to 70 ºC.The obtained results
have shown that there are differences in content of
secondary structures between wild type of HCC and its
mutants. For example the L68Q mutant contain the most
percentages of β-sheets of all tested proteins wheras
V57P mutant has the richest α-helix content.
Keywords: synchrotron radiation, hydrogen migration,
photodissociation, isoxazole, pyridine
*e-mail: [email protected]
Absorption of radiation by hydrocarbon molecules
can initiate their isomerization that usually provokes
extensive deformation of molecular structure and
reorganization of chemical bonds. In this rearrangement,
hydrogen migration plays an important role, because a
hydrogen atom or proton migrates from one site to
another within a molecule [1] what may lead to opening
of new reaction channels, frequently including
dissociation [2-5]. The hydrogen movement occurs
typically on a femtosecond time scale [3] and is faster
than the molecular bond breaking in dissociation. It can
therefore control chemical-bond-breaking and new bondforming processes in the biological radiation damage [5],
combustion [6], or catalytic studies [7].
In this context, the five and six-membered
heterocyclic hydrocarbons are ideal candidates to
characterize the hydrogen migration mechanisms in their
dissociation. Studies of these fundamental molecular
processes are important, especially from the viewpoint of
the DNA helix damage by the ionizing radiation. In
particular, the five-membered ring of isoxazole molecule
(Figure 1) may be discerned in the deoxyribose sugar of
DNA. On the other hand, pyridine, the six-membered
heterocyclic molecule (Figure 2), may be recognized in
the nucleic bases, adenine and guanine.
In the present study, the H atom migration was observed
in the photodissociation processes of the isoxazole and
pyridine molecules in the gas-phase, applying the
photon-induced fluorescence spectroscopy (PIFS) [8].
The measured fluorescence emission spectra revealed the
excited NH(A3Π) radicals detected by observation of
their A3Π→X3Σ‾ bands (Figure 1) together with emission
from the CH, CN and H excited dissociation fragments
[9, 10]. Neither isoxazole nor pyridine molecules contain
structural units built on NH group. Thus, observation of
the NH(A3Π→X3Σ‾) fluorescence gives a clear evidence
of the hydrogen migration prior to the photodissociation.
Acknowledgments: This research project has been financed by
the funds from the National Science Centre (Poland) granted on
the basis of decision no. DEC-2012/06/M/ST4/00036
___________________________________________________
[1] G. Guðmundsson, J. Hallgrímsson, T. Á. Jónasson,
Ó. Bjarnason, Brain. 95 (1972) 387.
[2] E. Levy, Expert Rev. Neurother. 8 (2008) 687.
doi:10.1586/14737175.8.5.687.
[3] R. Craig-Schapiro, M. Kuhn, C. Xiong, E.H. Pickering,
J. Liu, T. P. Misko, et al., PLoS ONE. 6 (2011) e18850.
[4] P. Garidel, H. Schott, BioProcess Int. (2006).
54
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
molecular ring and breakup of the molecular chain with
formation of several excited fragmentation products.
Figure 1. Emission spectrum of the isoxazole molecules
showing the NH(A3Π→X3Σ‾) bands.
In the studies of the photodissociation of isoxazole
molecule we have performed the density functional and
ab initio quantum chemical calculations [5] to propose
the mechanism of hydrogen relocation and formation of
the NH fragment:
Figure 2. The NH(A3Π) and H(n=5) fragmentation yields
obtained in the 16-70 eV photon energy range.
Acknowledgments: This work was in part financially
supported under the CALIPSO contract.
___________________________________________________
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
H. F. Schaefer III, Acc. Chem. Res. 12 (1979) 288.
K. M. Morgan et al., J. Org. Chem. 66 (2001) 1600.
T. Osipov et al., Phys. Rev. Lett. 90 (2003) 233002.
Y. H. Jiang et al., Phys. Rev. Lett. 105 (2010) 263002.
M. Zubek et al., J. Chem. Phys. 141 (2014) 064301.
A. Ratkiewicz, Reac. Kinet. Mech. Cat. 108 (2013) 545.
D. R. Killelea et al., Science 319 (2008) 790.
T. J. Wasowicz et al., Phys. Rev. A 83 (2011) 033411.
T. J. Wasowicz et al., J. Phys. B At. Mol. Opt. Phys. 45
(2012) 205103.
[10] T. J. Wasowicz et al., J. Phys. B At. Mol. Opt. Phys. 47
(2014) 055103.
The photon energy dependences of the measured
fragmentation yields show that the highly excited states,
the super-excited states, of the target molecules produced
in the photon absorption are intermediate states in fragmentation. The fluorescence yields of the excited
NH(A3Π) and H(n=5) fragments measured in pyridine in
the 16-70 eV region (Figure 2) show pronounced excitation bands that rise at about 10 eV above the first ionization potential of pyridine (9.26 eV). The dissociation of
the super-excited states proceeds by opening of the
55
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Our preliminary results shall be presented which
indicate that the cobalt and iron positions cannot be
described by only two (IP or OOP) possible locations,
which is in agreement with earlier Mossbauer studies [6].
P-20
Local electronic and crystal structures of FeTe
doped with cobalt
K. Żebrowska1*, M. Bagińska1, M. Wojdyła1,
E. Salas-Colera2, P. Zajdel1**
1Institute
of Physics, University of Silesia, ul. Universytecka 4,
40-007 Katowice, Poland
2SpLine CRG, European Synchrotron Radiation Facility,
CS40220, F-38043 Grenoble Cedex, France
Keywords: XAFS, iron telluride, cobalt
*e-mail: [email protected]
**e-mail: [email protected]
Due to inherent phase separation, it has been so far
impossible to grow ideally stoichiometric (1:1) tetragonal
(P4/nmm) iron telluride. The excess iron ions are located
in the inter-planar positions and usually represented as a
fraction x in a general formula Fe1+xTe [1], where x
ranges from about 4% to 17%. The additional iron has
been found to negatively correlate with the level of anion
site doping and subsequently with hindering the
superconductivity (SC), for example in the Fe(Te,Se,S)
series [2], where SC can be induced by doping with
selenium or small amounts of sulfur.
In our work, we attempted to create and investigate
compounds electronically equivalent to variable iron
stoichometry by substituting Fe with different transition
metals [3]. Here we report our results for single crystals
of FeTe doped with cobalt.
Samples several millimeter in size were grown by
solidification from melt method in the substitution range
x=0.01 to 0.1. The incorporation of dopant into host was
confirmed by WDS-SEM and observed trends in lattice
parameters obtained from single crystal diffraction.
However, it is not clear if Co is located in in-plane (IP)
or out-of-plane (OOP) positions See Fig. 1 due to low
level of doping and weak X-ray contrast between Co and
Fe.
In order to gain new insight into the problem we have
performed Fe K, Co K and Te L edge XAFS studies on
ESRF CRG SpLine [4] and MAXLAB-II I811 [5]
beamlines.
Figure 1. Possible locations of additional cobalt ions (a) inplane, (b) out-of-plane.
Acknowledgments: This work is supported by the Polish
National Science Centre grant No 2011/01/B/ST3/00425.
The research leading to these results has received funding from
the European Community's Seventh Framework Programme
(FP7/2007-2013) CALIPSO under grant agreement nº 312284
We would like to help N. Torapava for help during MAXLAB
experiment.
___________________________________________________
[1] W. Bao, Y. Qiu, Q. Huang, M. A. Green, P. Zajdel,
M. R. Fitzsimmons, M. Zhernenkov, M. Fang, B. Qian,
E. K. Vehstedt, J. Yang, H. M. Pham, L. Spinu, Z. Q.
Mao Phys. Rev. Lett. 102 (2009) 24700.
[2] P. Zajdel, Ping-Yen Hsieh, E. E. Rodriguez, N. P. Butch,
J. D. Magill, J. P. Paglione, P. Zavalij, M. R. Suchomel,
M. A. Green J. Am. Chem. Soc., 132 (2010) 13000.
[3] I. Kruk, P. Zajdel, Journal of Crystal Crowth, 401(1)
(2014) 608.
[4] G.R. Castro, Journal of Synchrotron Radiation, 5 (1998)
657.
[5] T.M. Grehk, P. O. Nilsson, Nucl. Instr. and Meth. in
Phys. Res. A 635 (2001) 467.
[6] A. Błachowski, K. Ruebenbauer, P. Zajdel,
E. E. Rodriguez, M. A. Green, J. Phys.: Condens. Matter
24 (2012) 386006.
56
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
[7]
Here we report our preliminary results of low
temperature powder XRD performed on ground single
crystals of FeTe doped with nickel, which reveals
splitting and suppression of the structural phase transition
in nickel doped system. The low temperature high
resolution X-Ray diffraction (HRPD) studies have been
carried out at ESRF CRG SpLine [5] beamline.
The evolution of structural transition was followed by
monitoring (112)t, (200)t peaks of the tetragonal unit
cell. Reflection (112)t is sensitive only to monoclinic
distortion and splits into (1-12)m and (112)m, whereas
(200)t splits into (200) and (020) in both monoclinic and
orthorhombic cells.
Sample with 1% doping (Figure 1) revealed only
small decrease of the transition temperature to 60K
without removing the monoclinic distortion. On the other
hand, doping with 5% of nickel showed significant
lowering of the transition temperature to 30 K and almost
complete suppression of monoclinic distortion.
P-21
Two step transition and suppression
of monoclinic distortion in FeTe doped
with nickel
M. Bagińska1*, M. Wojdyła1, K Żebrowska1, I. -L. Liu2,3,
N. P. Butch2,3, P. Zajdel1**
1Institute
of Physics, University of Silesia, ul. Universytecka 4,
40-007 Katowice. Poland
2NIST Center for Neutron Research, Gaithersburg,
MD 20899-6102
3Center for Nanophysics and Advanced Materials, Dept. of
Physics, University of Maryland, College Park, MD 20742
Keywords: XAFS, iron telluride, nickel
*e-mail: [email protected]
**e-mail: [email protected]
FeTe is a non-superconducting member of “11”
family of iron based superconductors [1]. It has been
found to become superconducting (SC) upon doping with
sulfur or selenium [1,2], which is precursored by
disappearance of the low temperature monoclinic (or
orthorhombic) distortion of the tetragonal lattice.
The other parameter critical for the SC is the amount
of the interstitial iron [1,2], which we want to control by
doping with nickel. Our preliminary low temperature
laboratory XRD on Cr and Ni [3] series did not reveal
any structural deformation upon cooling, which was a
very promising result. Unfortunately, high resolution
neutron powder diffraction carried at the NIST Center for
Neutron Research revealed that the distortion is still
present albeit gradually suppressed upon doping in Cr
series [4].
Figure 2. Splitting of temperatures of monoclinic and
orthorhombic transitions in Fe1.09Ni0.01Te.
Acknowledgments: This work is supported by the Polish
National Science Centre grant No 2011/01/B/ST3/00425.
We would like to help Drs Castro and Salas-Colera for help
during ESRF experiment.
___________________________________________________
[1] Wei Bao, Y. Qiu, Q. Huang, M. A. Green, P. Zajdel,
M. R. Fitzsimmons, M. Zhernenkov, M. Fang, B. Qian,
E.K. Vehstedt, J. Yang, H. M. Pham, L. Spinu, Z. Q. Mao
Phys. Rev. Lett. 102 (2009) 24700.
[2] P. Zajdel, Ping-Yen Hsieh, E. E. Rodriguez, N. P. Butch,
J. D. Magill, J. P. Paglione, P. Zavalij, M. R. Suchomel,
M. A. Green J. Am. Chem. Soc., 132 (2010) 13000.
[3] P. Zajdel, M. Zubko, J. Kusz, M. A. Green, Cryst. Res.
Technol., 45(12) (2010) 1316-1320.
[4] I. Kruk, P. Zajdel, Journal of Crystal Growth, 401(1)
(2014) 608.
[5] G. R. Castro, Journal of Synchrotron Radiation, 5 (1998)
657.
Figure 1. Monoclinic distorsion in Fe1.09Ni0.01Te seen by
splitting of (112) and (220) peaks of the tetragonal cell.
57
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
were later accompanied by measurements of Fe K and Te
L absorption.
P-22
Local electronic and crystal structures of FeTe
doped with nickel
M. Wojdyła1*, K Żebrowska1, M. Bagińska1, E. SalasColera2, P. Zajdel1**
1Institute
of Physics, University of Silesia, ul. Universytecka 4,
40-007 Katowice. Poland
2SpLine CRG, European Synchrotron Radiation Facility,
CS40220, F-38043 Grenoble Cedex, France
Keywords: XAFS, iron telluride, nickel
*e-mail: [email protected]
**e-mail: [email protected]
Figure 1. Possible locations of additional nickel ions (a) inplane, (b) out-of-plane.
Tetragonal (P4/nmm) iron telluride is known to
possess natural non-stoichiometry, usually represented as
a fraction x in a general formula Fe1+xTe [1]. The excess
iron ions are located in the inter-planar positions and
their content x ranges from about 4% to 17%. Due to
inherent phase separation, it has been so far impossible to
grow ideally stoichiometric (1:1) FeTe The additional
iron has been found to negatively correlate with the level
of anion site doping and subsequently with hindering the
superconductivity (SC), for example in the Fe(Te,Se,S)
series [2], where SC can be induced by doping with
selenium or small amounts of sulfur.
Here we report our results for single crystals of FeTe
doped with nickel, which is follow up on our ealier work
[3].
Single crystal several millimeter in size were grown
by solidification from melt method in the substitution
range x = 0.01 to 0.1. The incorporation of dopant into
host was confirmed by WDS-SEM and observed trends
in lattice parameters obtained from single crystal
diffraction. However, the SXRD study has not been
decisive in location of nickel due to low level of doping
and weak X-Ray contrast between Ni and Fe. There are
two main locations of cations in the FeTe lattice. An inplane (IP) position, which is in the centre of FeTe4
tetrahedron and out-of-plane (OOP) site, which is located
over the Te plane See Fig. 1.
In order to investigate a local environment around
nickel we have Ni K XAFS studies on ESRF CRG
SpLine [4] and MAXLAB-II I811 [5] beamlines. They
Our preliminary results shall be presented, which
indicate that the local crystallographic postions of nickel
cannot be described by only two (IP or OOP)
components, which is in agreement with many sites
suggested earlier by Mössbauer studies [6].
Acknowledgments: This work is supported by the Polish
National Science Centre grant No 2011/01/B/ST3/00425.
The research leading to these results has received funding from
the European Community's Seventh Framework Programme
(FP7/2007-2013) CALIPSO under grant agreement nº 312284
We would like to help N. Torapava for help during MAXLAB
experiment.
___________________________________________________
[1] W. Bao, Y. Qiu, Q. Huang, M. A. Green, P. Zajdel,
M. R. Fitzsimmons, M. Zhernenkov, M. Fang, B. Qian,
E.K. Vehstedt, J. Yang, H. M. Pham, L. Spinu, Z.Q. Mao
Phys. Rev. Lett. 102 (2009) 24700.
[2] P. Zajdel, Ping-Yen Hsieh, E. E. Rodriguez, N. P. Butch,
J. D. Magill, J. P. Paglione, P. Zavalij, M. R. Suchomel,
M. A. Green J. Am. Chem. Soc., 132 (2010) 13000.
[3] I. Kruk, P. Zajdel, Journal of Crystal Crowth, 401 (2014)
608.
[4] G. R. Castro, Journal of Synchrotron Radiation, 5 (1998)
657.
[5] T .M. Grehk and P. O. Nilsson, Nucl. Instr. and Meth. in
Phys. Res. A 635 (2001) 467.
[6] A. Błachowski, K. Ruebenbauer, P. Zajdel,
E. E. Rodriguez and M. A. Green, J. Phys.: Condens.
Matter 24 (2012) 386006.
58
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
methanol–ethanol mixture) and quasi-hydrostatically up
to 10 GPa with a small maximum of nonhydrostaticity at
6 GPa [4]. Gold has been chosen as a pressure standard
because of its moderate compressibility, chemical
inertness, and large X-ray scattering power [5]. A small
lump of gold with a purity of 999.9 (four nines fine) and
an average particle size of 30 µm was put in the hole of a
rhenium gasket.
P-23
Li0.95Mn2.05O4 under high pressure and at
elevated temperature in DAC
P. Piszora1*, J. Darul1, C. Popescu2, F. Fauth2
1
Department of Materials Chemistry, Faculty of Chemistry,
Adam Mickiewicz University, Umultowska 89b,
61-614 Poznań, Poland
2 CELLS-ALBA Synchrotron Light Source, 08290 Cerdanyola
del Valles, Barcelona, Spain
Keywords: high pressure, high temperature, lithium-manganese
spinel
*e-mail: [email protected]
A displacive crystal distortion to lower symmetry that
cooperatively removes a localized-electron orbital
degeneracy so as to leave the atoms in the centre of
symmetry of their distorted sites has been observed in
many manganese oxides. Moreover, strong Jahn-Teller
electron-phonon coupling has been proposed as the
crucial component which localizes the eg electrons as
polarons. High pressure and high temperature are a
means to tune such an interplay between lattice and
electronic degrees of freedom in the lithium manganese
spinel [1,2].
The Li0.95Mn2.05O4 spinel sample was obtained from
the appropriate amounts of thoroughly mixed powders of
-Mn2O3 and Li2CO3 (99.0% Merck) by thermal
treatment in air at 1048 K. After heating, the specimen
was quenched rapidly in solid CO2. Structural analyses
showed the expected stoichiometry of the obtained
powder and confirmed that no spurious phases were
present.
The structural properties of Li0.95Mn2.05O4 under
pressure and at elevated temperature were studied up to
13 GPa by X-ray powder diffraction at the MSPD-BL04
beamline [3] of the ALBA Synchrotron Light Source
using monochromatic radiation ( = 0.4246 Å).
Diffraction patterns were recorded on image plates and
then integrated [8] to yield intensity vs 2 diagrams.
For HP/HT experiments, sample was loaded in the
140-μm-diameter hole of an rhenium gasket inside a
membrane-type diamond anvil cell (DAC) with a
polydimethyl-siloxane oil of type ‘Rhodorsil 47V1000’
(VCR) as the pressure transmitting medium, which
behaves hydrostatically up to 3 GPa (similar to the 4 : 1
Figure 1. Pressure-induced evolution of XRD pattern.
Li0.95Mn2.05O4 was studied by synchrotron X-ray
diffraction isothermally at ambient temperature and at
107 °C under pressures up to 12 GPa. Usually the
cooperative Jahn–Teller (JT) distortion is continuously
reduced with increasing pressure. However, we obtained
a strong indication that the JT effect and the concomitant
orbital order are induced with pressure even if in the
initial sample the cooperative Jahn–Teller distortion has
been suppressed with temperature.
Acknowledgments: These experiments were performed at the
MSPD-BL04 beamline at ALBA Synchrotron with the
collaboration of ALBA staff.
___________________________________________________
[1]
[2]
[3]
[4]
[5]
59
N. Ishizawa, K. Tateishi, S. Oishi, S. Kishimoto, Am.
Mineral. 99 (2014) 1528.
J. Darul, C. Lathe, P. Piszora, R. Soc. Chem. Adv.
4 (2014) 65205.
F. Fauth, I. Peral, C. Popescu, M. Knapp, Powder Diffr.
28 (2013) S360.
S. Klotz, J. C. Chervin, P. Munsch, G. Le Marchand,
J. Phys. D: Appl. Phys. 42 (2009) 075413.
K. Takemura, A. Dewaele, Phys. Rev. B 78 (2008)
104119.
KSUPS 2015: Abstracts / Extended abstracts / Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
At the first stage the concentrated solutions of gemini
surfactants (over cmc) were characterized by the use of
small angle scattering of synchrotron radiation technique
(SR-SAXS).
High resolution DOSY NMR revealed some unusual
aggregation behavior, related to high polydispersity of
surfactant aggregates for the concentrations higher than
CMC. Obtained cmc's values ranged from 0.01 mM up to
1 mM. Furthermore pH dependence was observed as a
result of electrostatic interaction between imidazolium
ions.
The complex dynamics of spacer was confirmed by
FT-IR studies. Additionally selected systems were
characterized by FFC spectroscopy.
P-24
The dynamics of micellization of gemini
imidazolium surfactants studied by NMR, FT-IR
and SR-SAXS
K, Szutkowski, Z. Pietralik, M. Kozak*
Department of MaclomolecularPhysics, Faculty of Physics,
Adam Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
Keywords: synchrotron radiation, small angle X-ray scattering,
cmc, dicationic surfactants
*e-mail: [email protected]
Acknowledgments: This research project has been financed by
the funds from the National Science Centre (Poland) granted on
the basis of decision no. DEC-2011/01/B/ST5/00846.
___________________________________________________
Gemini surfactants, also known as dimeric or
dicationic surfactants are recently studied as components
of drug delivery systems, especially for gene therapy
[1,2]. This group of surfactants has cmc (critical
micellization concentration) much lower than that of a
monomeric surfactants with equivalent aliphatic chain
length [3].
The aim of this study was the characterization of
structural parameters and cmc values characterizing the
solutions of selected gemini surfactants (3,3’-[α,ω(dioxaalkane)] bis(1-alkylimidazolium) chlorides).
The critical micellization concentration for
imidazolium gemini surfactans with spacer widths
ranging from 2 to 8 methylene groups were obtained.
[1] H. Yin, R.L. Kanasty, A. A. Eltoukhy, A. J. Vegas,
J. R. Dorkin, D. G. Anderson, Nature Reviews Genetics 15
(2014) 541.
[2] P. Luciani, C. Bombelli, M. Colone, L. Giansanti,
S. Ryhaenen, V. M. J. Saily, G. Mancini,
P. K. J. Kinnunen Biomacromolecules 8 (2007) 1999.
[3] R. Zana, Advances in Colloid and Interface Science 97
(2002) 205.
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Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Regular Contribution
Działalność Naukowa Pracowni Spektroskopii Optycznej Półprzewodników Instytutu Fizyki
Uniwersytetu Jagiellońskiego. Udział w badaniach z zastosowaniem
promieniowania synchrotronowego
A. Kisiel*
Instytut Fizyki im. M. Smoluchowskiego, Uniwersytet Jagielloński, ul. prof. St. Łojasiewicza 11, 30-348 Kraków
*e-mail: [email protected]
jako podstawowe materiały półprzewodnikowe do
wytwarzania
tranzystorów.
Zainteresowanie
się
spektroskopią optyczną półprzewodników było naturalną
konsekwencją doświadczenia nabytego w zakończonych
badaniach w zakresie spektroskopii atomowej. Prof.
H. Niewodniczański dostrzegł również przyszłościowe
perspektywy
badawcze
spektroskopii
optycznej
półprzewodników. Pomimo że do tego czasu
w Zakładzie Fizyki Doświadczalnej były głównie
prowadzone badania w zakresie spektroskopii atomowej,
prof. H. Niewodniczański zaakceptował podjęcie nowego
kierunku badań spektroskopowych i aktywnie wspierał
ich rozwój aż do swojej śmierci w grudniu 1968 roku.
Gorąca zachęta do podjęcia tych badań nadeszła
również od wysoko cenionych specjalistów w zakresie
fizyki
półprzewodników
profesorów
Wiesława
Wardzyńskiego z Instytutu Fizyki Doświadczalnej
Uniwersytetu Warszawskiego
Wprowadzenie
Odbudowanie fizyki doświadczalnej w Uniwersytecie
Jagiellońskim po zniszczeniach II wojny światowej było
priorytetem prof. H. Niewodniczańskiego, który po
objęciu w roku 1946 II Katedry Fizyki Doświadczalnej
zorganizował i istotnie ożywił działalność naukową.1
Jako uznany w świecie naukowym badacz w zakresie
spektroskopii atomowej, w kierowanej Katedrze Fizyki
Doświadczalnej (KFD), przemianowanej w połowie lat
pięćdziesiątych ubiegłego stulecia na Zakład Fizyki
Doświadczalnej (ZFD), proponował zwykle nowo
przyjętym
współpracownikom
podjęcie
badań
naukowych w dziedzinie spektroskopii atomowej. Autor
tego artykułu, przyjęty w roku 1953 na asystenturę
w KFD, również otrzymał taką propozycję. Dotyczyła
ona podjęcia badań stosunków natężeń w multipletach
linii widmowych wodoropodobnych jonów aluminium
i krzemu tzn. jonów z jednym elektronem walencyjnym.
Rysunek 2. Wspólny spacer po Czantorii w czasie
Międzynarodowej
Szkoły
Fizyki
Półprzewodników
w Jaszowcu. Prof. W. Wardzyński (drugi z lewej) i prof.
W. Giriat w środku grupy uczestników Szkoły.
Rysunek 1. Profesor H.Niewodniczański.
Po zakończeniu przewidywanego programu badań
rozprawą doktorską i publikowanymi artykułami2,
szczególne zainteresowanie naukowe autora artykułu
wzbudzało, rozpoczęte w Europie i USA w połowie lat
pięćdziesiątych ubiegłego wieku, eksperymentalne
analizowanie
struktury
elektronowej
pasma
walencyjnego i pasma przewodnictwa ciał stałych przy
użyciu metod spektroskopii optycznej3. Badania te
dostarczały fundamentalne informacje o strukturze
elektronowej ciał stałych. Okazały się szczególnie cenne
przy zbieraniu informacji o strukturze elektronowej pasm
walencyjnego i przewodnictwa germanu4 i krzemu5,
robiących wówczas oszołamiącą karierę w elektronice,
i Witolda Giriata z Instytutu Fizyki PAN w Warszawie.
Prof. W. Giriat, jako wybitny specjalista w zakresie
technologii wytwarzania monokryształów związków
półprzewodnikowych, zaoferował stałe dostarczanie,
niezbędnych do badań, bardzo wysokiej jakości
monokrystalicznych materiałów półprzewodnikowych.
Dało to podwaliny wieloletniej, wzajemnej bardzo
efektywnej współpracy. Wykorzystując wymienione
powyżej sprzyjające okoliczności, w roku 1965
w Zakładzie Fizyki Doświadczalnej IF UJ powstała
Pracownia Spektroskopii Optycznej Półprzewodników
(PSOP).
61
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
w zakresie obliczeń teoretycznych struktury elektronowej
krystalicznych ciał stałych. W czasie tego pobytu
powstała publikacja, przygotowana wspólnie z drugim
stypendystą dr Peterem M. Lee z Uniwersytetu
w Lancaster (GB). Praca ta dotyczyła teoretycznego
opisu istotnej roli poprawek relatywistycznych przy
powstawaniu przejścia od prostej do odwróconej przerwy
wzbronionej w strukturze
elektronowej potrójnych
związków Cd1-xHgxTe [10]. Ta publikacja i wcześniejsze
prace eksperymentalne opisujące strukturę elektronową
roztworów stałych CdxHg1-xTe [5, 7] i ZnxCd1-xTe [6]
złożyły się na rozprawę habilitacyjną autora artykułu
[8, 9]. W trakcie pobytu na stypendium Prof. F. Bassani
zaproponował by prowadzone w PSOP ZFD
w Krakowie, eksperymentalne badania fundamentalnego
odbicia półprzewodników w zakresie energii 1,8 – 6 eV,
rozszerzyć
na
zakres
próżniowego
nadfioletu
Badania eksperymentalne w Pracowni Spektroskopii
Optycznej Półprzewodników (PSOP)
Działalność badawczą PSOP zapoczątkowały próby
przystosowywania
próżniowego
spektrografu
z pryzmatem i soczewkami z krystalicznego fluorytu,
używanego we wcześniejszych badaniach widm
liniowych Si IV6 do badań współczynników absorpcji
i odbicia światła półprzewodników. Spektrograf ten
został zakupiony w Niemczech przez profesora
H. Niewodniczańskiego w roku 1946 za środki
otrzymane od Niemiec w ramach reparacji wojennych
wypłacanych za mienie zrabowane w czasie II wojny
światowej.
Odpowiednie
przystosowanie
tego
spektrografu do badań optycznych półprzewodników
napotkało jednakże na szereg poważnych trudności
technicznych, które ostatecznie przesądziły o rezygnacji
z adaptacji spektrografu fluorytowego do dalszych badań
i o konieczności podjęcia starań o zakup odpowiedniego
monochromatora na obszar próżniowego nadfioletu.
Równocześnie z pracami nad adaptacją spektrografu był
budowany jednowiązkowy odbiciomierz fotoelektryczny
na obszar widzialny i bliskiego nadfioletu (od 600 do 200
nm) co odpowiada energii promieniowania od ok.
1,8 – 6 eV. Uruchomiony odbiciomierz działał
w systemie „wiązki białej”, tzn. że skupiona na próbce
„biała” wiązka światła ze źródła po odbiciu od próbki
była skupiana na szczelinie wejściowej monochromatora
analizującego rozkład widmowy wiązki. Natężenie
wiązki było mierzone przez fotopowielacz umieszczony
na szczelinie wyjściowej monochromatora i rejestrowane
po wzmocnieniu przez fazoczuły elektroniczny układ
detekcyjny. Przy użyciu tego układu pomiarowego
zostały uzyskane i opublikowane w roku 1969 pierwsze
wyniki badań dotyczące analizy widm odbicia światła dla
kilku
monokrystalicznych
potrójnych
związków
półprzewodnikowych CdHgTe, wytworzonych przez
Roberta Gałązkę w laboratorium technologicznym
Instytutu
Fizyki
Doświadczalnej
Uniwersytetu
Warszawskiego [4, 5]7. Przy użyciu tego odbiciomierza
fotoelektrycznego kontynuowano również dalsze badania
fundamentalnego odbicia światła dla monokrystalicznych
roztworów stałych CdxHg1-xTe [5, 7] i ZnxCd1-xTe [6].
Rozwijane w PSOP badania widm odbicia światła
półprzewodników stały się motorem do sformułowania
w październiku 1969 roku wniosku Instytutu Fizyki UJ
o włączenie do Centralnego Planu 5-letniego badań
naukowych i rozwoju technicznego na lata 1971 – 1975,
badań optycznych ciała stałego w zakresie próżniowego
nadfioletu 6 – 10 eV, w oparciu o posiadaną bazę
aparaturową oraz budowane konwencjonalne wodorowe
i helowe źródła promieniowania elektromagnetycznego
świecące w obszarze próżniowego nadfioletu. Aby
sprostać tym planom PSOP została wzmocniona,
przyjętymi na asystentury do ZFD, mgr Martę Zimnal
i mgr Barbarę Pukowską.
Na przełomie roku 1970 i 1971 autor artykułu, jako
stypendysta Rządu Republiki Włoch, odbył półroczny
staż w Instytucie Fizyki Uniwersytetu Rzymskiego
„La Sapienza” w grupie teoretycznej prof. Franco
Bassaniego, wybitnego specjalisty w skali światowej
Rysunek 3. Prof. G.F. Bassani, inicjator współpracy włoskopolskiej.
(10 – 200 eV) z użyciem promieniowania synchrotronowego z 1,1 GeV synchrotronu usytuowanego
w INFN (Istituto Nazionale di Fisica Nucleare) we
Frascati. Badania odbicia światła półprzewodników
miały być prowadzone we współpracy z kierowaną przez
prof. F. Bassaniego grupą Solidi Roma8, posiadającą
bezpośredni
dostęp
do
wykorzystujących
promieniowanie synchrotronowe dwu optycznych linii
pomiarowych we Frascati. Podjęcie wspólnych włoskopolskich
eksperymentalnych
badań
optycznych
rozszerzało i nakładało wyższe wymagania merytoryczne
na rozpoczęte wcześniej w PSOP badania w zakresie
spektroskopii optycznej półprzewodników. Aby sprostać
tym wymaganiom w kolejnych latach współpracy
doskonalono technikę pomiaru fundamentalnego odbicia
światła i szczegółowo analizowano czynniki fizyczne
(naprężenia wewnętrzne, wpływ obróbki mechanicznej i
trawienia na chropwatość powierzchni) badanych
materiałów. Włączenie się do badań z zastosowaniem
promieniowania synchrotronowego miało kolosalne
znaczenie dla rozwoju, opisanej szczegółowiej
w paragrafie 4, aktywności naukowej PSOP.
62
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Po objęciu przez autora artykułu w październiku 1973
roku kierownictwa Zakładu Fizyki Ogólnej (ZFO), PSOP
została automatycznie przeniesiona z ZFD do ZFO wraz
ze współpracownikami mgr Jolantą Dydecką,
mgr Barbarą Pukowską i mgr Martą Zimnal oraz
technikiem elektronikiem Romualdem Samsonem.
(np. CuInS2) analizowane pod kątem zastosowań
fotowoltaicznych.
Rysunek 5. Obrady Międzynarodowej Konferencji Cienkich
Warstw w Budapeszcie. W pierwszym rzędzie trzeci od lewej
prof. J.K. Viscacas, w drugim rzędzie trzeci od lewej autor
artykułu, obok doc. S. Ignatowicza.
Rysunek 4. Prof. W. Giriat i autor artykułu w przerwie obrad
Międzynarodowej
Szkoły
Fizyki
Półprzewodników
w Jaszowcu.
Po nawiązaniu współpracy naukowej z kilkoma
pracowniami technologicznymi były prowadzone
badania fundamentalnego odbicia dla cienkich warstw
ZnTe i CdHgTe [14, 17, 21, 22, 25, 26, 43] oraz cienkich
warstw Zn2As3 [13, 18]. Nowo zaangażowani
wspólpracownicy Marek Podgórny i Andrzej Rodzik
prowadzili badania fundamentalnego odbicia światła
w funkcji składu i temperatury monokryształów
roztworów stałych CdHgTe [19, 20, 23] a Katarzyna
Karnicka-Mościcka dla cienkich warstw Cd3As2 [27, 37,
64, 65, 72]. Wszystkie te badania były prowadzone przy
użyciu odbiciomierza fotoelektrycznego w systemie
„wiązki białej”, w którym uciążliwą technicznie obróbkę
danych pomiarowych zastąpiono układem automatycznej
fazoczułej rejestracji danych [15]. Układ ten znacznie
podwyższał dokładność pomiarów i szybkość rejestracji
rezultatów doświadczalnych. Realizując cele naukowe
PSOP zapowiadane w projekcie współpracy z grupą
Solidi Roma, dotyczące prowadzenia komplementarnych
badań całego obszaru fundamentalnego odbicia
półprzewodników, w roku 1975 został zakupiony przez
IF UJ dla PSOP 1-metrowy siatkowy monochromator
próżniowy firmy Hilger & Watts E766. Na bazie tego
monochromatora został zbudowany i uruchomiony
dwuwiązkowy odbiciomierz na zakres próżniowego
nadfioletu od 5 – 11 eV z automatyczną rejestracją
danych [40].
Z pomocą
tego spektrometru
przeprowadzono badania wpływu temperatury na
współczynniki absorpcji i odbicia dla CdF2 [47,57] oraz
analizę fundamentalnego odbicia dla monokryształów
CdxHg1-xTe [56,59] i ZnTe [60]. W celu udoskonalenia
pomiarów fundamentalnego odbicia półprzewodników w
zakresie energii 1,5 – 6 eVzbudowano w PSOP kilka
wersji dwuwiązkowego odbiciomierza fotoelektrycznego
z automatyczną, fazoczułą rejestracją danych współpracującą on line z komputerem [73, 95].
W skonstruowanych odbiciomierzach wiązka światła
monochromatycznego była dzielona na dwie części:
jedna z nich oświetlała badaną próbkę i odbita od niej
padała na fotopowielacz mierzący jej natężenie, druga
Fundamentalne odbicie światła półprzewodników jest
niezwykle czułe na jakość badanych monokryształów
i stan powierzchni odbijającej, w związku z tym bez
dobrych, wszechstronnie atestowanych materiałów
półprzewodnikowych dostarczonych przez renomowane
pracownie technologiczne nie można było myśleć
o wiarygodnych badaniach. Ze względu na bardzo
wysokie koszty uruchomienia technologii wytwarzania
dobrej jakości atestowanych monokryształów i cienkich
warstw materiałów półprzewodnikowych potrzebnych do
badań, została nawiązana przez PSOP nieformalna,
obopólnie korzystna współpraca z kilkoma krajowymi
i zagranicznymi laboratoriami technologicznymi. PSOP
współpracowała z laboratoriami technologicznymi
Instytutu
Fizyki
Doświadczalnej
Uniwersytetu
Warszawskiego (prof. R.R. Gałązka, prof. W. Giriat)),
Instytutu Fizyki PAN w Warszawie (prof. W. Giriat i A.
Mycielski),
Instytutu Tele-Radiotechnicznego w
Warszawie (doc. S. Ignatowicz), Instytutu Fizyki
Politechniki Wrocławskiej (prof. J. Pawlikowski),
Zakładu Fizyki PAN w Zabrzu (doc. L. Żdanowicz)
i Instytutu Fizyki Technicznej Wojskowej Akademii
Technicznej
w
Warszawie
(prof.
J.
Żmija
i M. Demianiuk), a także z dr R.D. Tomlinsonem
z Departamentu Inżynierii Elektrycznej i Elektroniki
(Department of Electronic and Electrical Engineering)
Uniwersytetu w Salfort (Wielka Brytania), prof. J.K.
Viscacasem z Instytutu Fizyki Uniwersytetu w Wilnie
i prof. W.J. Potykiewiczem z Instytutu Fizyki
Uniwersytetu
Kijowskiego.
Przez
wiele
lat
kontynuowano również współpracę z prof. W. Giriatem
po jego emigracji do Wenezueli, gdzie w Instituto
Venezolano de Ivestigationes Cientificas, Centro
de Fisica (IVIC) w Caracas wytwarzał obok
monokryształów związków półprzewodnikowych grupy
II-VI z metalami przejściowymi również bardzo
wysokiej jakości monokrystaliczne związki typu II III2
VI4 (np. CdIn2S4, ZnIn2S4, ZnGa2Se4, CdGa2S4) i I III VI2
63
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
część, jako wiązka odniesienia, za pomocą układu luster
była kierowana wprost na drugi fotopowielacz.
Tak więc obok podstawowych badań struktury
elektronowej pasm walencyjnego i przewodnictwa wielu
związków
półprzewodnikowych,
wymagających
eliminacji efektów zaburzających poprawny pomiar [13,
14, 16, 17, 18-23, 27, 30, 31, 37, 47, 56, 57, 59-61, 66,
72-74, 81], siłą rzeczy, rozwinęły się również
diagnostyczne badania niedoskonałości struktury
krystalicznej [25, 31, 38, 55, 58, 66, 67, 71, 81, 84]
i naprężeń wewnętrznych w kryształach i polikrystalicznych cienkich warstwach [25, 45, 55, 58, 61,
62] oraz nierówności powierzchni odbijających [38, 4146, 49-51, 65].
Badania wpływu nierówności powierzchni na widmo
optyczne
metali
i
półprzewodników
znalazło
zastosowanie jako nieniszcząca metoda diagnostyki
powierzchni metalizowanego i niemetalizowanego
kwarcu [41-44, 46, 49-51]. Metoda ta była
opracowywana, w ramach programów węzłowych
i resortowych, dla Instytutu Tele-Radiotechnicznego
w Warszawie.
W PSOP przybywało współpracowników. Razem
z podstawowym składem osobowym: Ewą CzarneckąSuch, Barbarą Pukowską, Markiem Podgórnym,
Andrzejem Rodzikiem, Markiem Turowskim i Martą
Zimnal-Starnawską, w rozwoju badań uczestniczyli
doktoranci: Barbara Oleś, Katarzyna Karnicka-Mościcka,
Marek Czyżyk, Józef Oleszkiewicz, Dorota Dębowska,
Jacek Goniakowski, Artur Hołda i Paweł Zajdel oraz
spore grono magistrantów. Część doktorantów po
uzyskaniu stopni doktora została zatrudniona na etatach
w PSOP ZFO9. Prowadzone badania dostarczały szereg
nowych i interesujących rezultatów. Szeroko zakrojone
badania struktury elektronowej półprzewodnikowych
związków mieszanych CdxHg1-xTe zostały nagrodzone
w roku 1978 zespołową nagrodą Ministra Nauki
i Szkolnictwa Wyższego i Techniki III stopnia10.
Marek Turowski po obronie doktorskiej w roku 1982
wyjechał na stypendium do Instytutu Fizyki
w Uniwersytecie Neymegen (Holandia) a następnie do
Departamentu Fizyki Uniwersytetu w Wisconcin (USA),
gdzie pod kierunkiem prof. Giorgio Margaritondo brał
udział w badaniach fotoemisji elektronowej krzemu
oraz heterozłączy na orientowanych monokryształach
GaAs z użyciem promieniowania synchrotronowego
z synchrotronu w Wisconcin [87-93]. Niestety po
powrocie do Polski z tego stażu naukowego zrezygnował
z pracy w IF UJ i wyjechał na stałe do USA.
W drugiej połowie lat siedemdziesiątych ubiegłego
stulecia została zapoczątkowana również współpraca
naukowa z Wilnem i Kijowem na bazie zawartych umów
o współpracy bezpośredniej pomiędzy Uniwersytetami
Jagiellońskim, Wileńskim i Kijowskim. Wizyty prof.
J.K.Viscakasa i A. Żyndulisa z Uniwersytetu
Wileńskiego
oraz
prof.
W.J.
Potykiewicza
z Uniwersytetu Kijowskiego zaowocowały wspólnymi
publikacjami [31,60]. Po przerwie natury politycznej, w
latach dziewięćdziesiątych ożywiły się kontakty
naukowe z Instytutem Fizyki Uniwersytetu Kijowskiego
oraz zostały nawiązane kontakty naukowe z prof. V.I.
Strikhą i H. Pieką oraz z dr P.W. Żukowskim z Instytutu
Fizyki Uniwersytetu w Mińsku. Wynikiem współpracy
A. Rodzika i E. Czarneckiej-Such na temat fizyko-
Rysunek 6. A. Rodzik przy dwuwiązkowym odbiciomierzu
z automatyczną rejestracją danych.
W takim układzie był możliwy pomiar
współczynnika odbicia (lub absorpcji), z wyeliminowaniem efektów związanych z „podświetlaniem wiązką
białą” badanych materiałów oraz fluktuacji natężenia
padającego światła. Budowane zestawy pomiarowe
odznaczały się bardzo wysoką czułością i dokładnością
pomiaru, przewyższającą czułość i zdolność rozdzielczą
spektrometrów komercyjnych produkowanych przez
renomowane
firmy
zagraniczne
w
latach
siedemdziesiątych i osiemdziesiątych ubiegłego wieku.
Należy podkreślić, że powszechnie stosowane
w spektroskopii optycznej do końca lat pięćdziesiątych
ubiegłego wieku spektrografy z rejestracją widm
optycznych na kliszy fotograficznej, w ciągu zaledwie
dziesięciu lat, zostały zastąpione w laboratoriach
naukowych przez monochromatory z fotoelektryczną
rejestracją natężeń widm optycznych ( np. przy użyciu
fotopowielaczy)
i
fazoczułych
wzmacniaczy
współpracjących on line z komputerem. Rozwój techniki
pomiarowej w PSOP nadążył za tą rewolucyjną
przebudową światowej techniki pomiarowej w spektroskopii optycznej.
W latach 1977 – 1980 zostały podjęte próby
zwiększenia dokładności opisu struktury elektronowej
badanych materiałów poprzez zastosowanie metod
modulacyjnych w badaniach spektroskopowych [35, 52].
Jednakże ze względu na obecność dodatkowych
charakterystycznych efektów w odbiciowych widmach
modulacyjnych, nie rozwijano dalej tej metodyki
i skierowano wszystkie wysiłki na uzyskanie jak
najwyższej
czułości
i
zdolności
rozdzielczej
w bezpośrednim pomiarze odbicia światła.
Ze
względu
na
bardzo
silną
zależność
fundamentalnego odbicia od doskonałości struktury
krystalicznej badanych materiałów oraz stopnia czystości
i chropowatości powierzchni próbek, prowadzone
badania dostarczały nie tylko podstawowe informacje
o strukturze elektronowej materiałów, ale również
wiedzę
o
niedoskonałościach
i
naprężeniach
wewnętrznych
struktury
krystalicznej
badanych
materiałów a także o właściwościach powierzchni
odbijającej.
64
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
chemicznych własności powierzchni CdMnTe oraz
własności dielektrycznych i optycznych Si implantowanego jonami były publikacje [167, 169, 173, 176,
189, 192].
Rzymskiego II „Tor Vergata” (formalnie potwierdzona
umową o współpracy bezpośredniej w roku 1993).
Wczesna działalność naukowa PSOP została
zaprezentowana w roku 1983 w artykule opublikowanym
w czasopiśmie Optica Applicata [83]. Pełna działalność
badawcza, wchodzących w skład Zakładu Fizyki
Ogólnej,
Pracowni
Spektroskopii
Optycznej
Półprzewodników, Pracowni Spektroskopii Interferencyjnej i Pracowni Spektroskopii Molekularnej,
została opisana w artykule zamieszczonym w roku 2014
na stronie internetowej IF UJ11.
Powstanie i działalność grupy teoretycznej PSOP
Do właściwej interpretacji eksperymentalnych widm
współczynników absorpcji i fundamentalnego odbicia
światła niezbędne jest porównywanie ich z bardzo
zaawansowanym opisem teoretycznym struktury
elektronowej półprzewodników. W związku z tym
w PSOP zaistniała potrzeba wykształcenia grupy
teoretyków specjalizujących się w obliczeniach
teoretycznych
dotyczących struktury elektronowej
półprzewodników i metali. Korzystając z licznych
dyskusji ze współpracującymi z PSOP teoretykami prof.
F. Bassanim i jego uczniem F. Casulą, współautorem
wspólnej z autorem tego artykułu teoretycznej publikacji
na temat struktury elektronowej CdxHg1-xTe [35], M.
Podgórny a następnie M. Czyżyk rozpoczęli samodzielne
teoretyczne obliczenia struktury elektronowej CdTe
i HgTe [53] oraz CdxHg1-xTe [48], a także analizy
poprawek w opisie potencjału miseczkowego
stosowanego w obliczeniach struktury elektronowej [85].
W zadaniu tworzenia w PSOP wyspecjalizowanej grupy
teoretyków szczególnie ważne wsparcie otrzymaliśmy od
prof. Joachima Treutscha, kierownika Katedry Fizyki
Teoretycznej Uniwersytetu w Dortmundzie12. Prof.
J. Treutsch, wybitny specjalista w badaniach
teoretycznych struktury elektronowej ciał stałych, dzięki
swym wpływom,
ułatwił uzyskanie rocznego
stypendium im. Aleksandra von Humboldta dla
M. Czyżyka i dwuletniego stypendium dla
M. Podgórnego oraz przyjął bezpośrednią opiekę nad
obydwoma stypendystami. M. Podgórny opublikował
wspólnie ze współpracownikami prof. M. Treuscha
J. Pollmannem [111] i D. Wagnerem [112] bardzo cenne
rezultaty naukowe dotyczące obliczeń struktury
elektronowej
roztworów
stałych
SiGe
oraz
strukturalnych i magnetycznych przejść fazowych
w stopach metali przejściowych. W wyniku dalszych
badań M. Podgórny opublikował kilka interesujących
wyników teoretycznych
na temat magnetyzmu
wędrownego w ciałach stałych. Publikacje te stanowiły
podstawę
doskonałej
dysertacji
habilitacyjnej,
wyjaśniającej nierozwiązany od końca dziewiętnastego
wieku, problem bardzo niskiej rozszerzalności termicznej
inwaru [115, 130-132].
Przyjazna pomoc i zaangażowanie prof. J. Treuscha,
przy wykształceniu dla PSOP dojrzałych naukowo
młodych teoretyków, owocowała przez wiele lat.
Z upływem czasu powstałą grupę teoretyczną wzmocnili:
J. Goniakowski – doktorant M. Podgórnego, ściśle
współpracujący z nami R. Markowski, pracownik
Zakładu Techniki Komputerowej, oraz doktoranci PSOP
Rysunek 7. Wizyta w Instytucie Radiofizycznym Uniwersytetu
Kijowskiego. Od lewej E.V. Buzaneva, A. Rodzik i E.
Czarnecka-Such.
Ze względu na wspólne z PSOP zainteresowania
badaniami z użyciem promieniowania synchrotronowego
w roku 1996 dołączył do ZFO Marek Stankiewicz
i utworzył Pracownię Spektroskopii Molekularnej
(PSM). Przedmiotem jego badań były procesy
i mechanizmy relaksacji prostych drobin tzn. badania
fotodysocjacji
molekularnej,
foto-fragmentacji,
fotoemisji elektronowej molekuł i fotojonizacji przy
użyciu promieniowania synchrotronowego z synchrotronu SRS w Daresbury (Wielka Brytania)
i synchrotronu MAX II (Szwecja). Rezultaty tych badań
zostały opublikowane w kilkunastu artykułach [227-230,
232-237, 251, 253-257]. W utworzonej Pracowni
Spektroskopii Molekularnej ZFO, M. Stankiewicz obok
badań z użyciem promieniowania synchrotronowego
wykorzystał do badań fotodysocjacji drobin posiadany
przez PSOP ZFO 1-metrowy monochromator próżniowy
Hilger&Watts oraz laser Nd/YAG z 2 i 3 harmoniczną.
Na bazie tych urządzeń został zbudowany analizator
czasu przelotu z detektorem mikrokanalikowym
i wielokanałowym przetwornikiem czas/cyfra o wysokiej
zdolności rozdzielczej oraz komputerową akwizycją
danych doświadczalnych. W budowie aparatury
i badaniach uczestniczył doktorant Piotr Winiarczyk oraz
magistranci.
Istotnym czynnikiem działalności naukowej PSOP
ZFD a następnie PSOP ZFO była współpraca naukowa
rozwijana z Włochami, Republiką Federalną Niemiec,
Wielką Brytanią, Szwecją i ZSSR. Szczególnie ścisła
i długotrwała współpraca PSOP ułożyła się z Instytutem
Fizyki, a następnie Departamentem Fizyki Wydziału
Inżynierii Uniwersytetu Rzymskiego I „La Sapienza”
i z Laboratorium Narodowym we Frascati (Laboratori
Nazionali di Frascati (LNF)) przynależącym do Instytutu
Narodowego Fizyki Jądrowej (Istituto Nazionale
di Fisica Nucleare (INFN)). Ponadto przez szereg lat
trwała
współpraca
z
Departamentem
Fizyki
Uniwersytetu w Trento (od 1986 roku, umowa podpisana
w roku 1989) oraz z Instytutem Fizyki Uniwersytetu
65
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
ZFO J. Oleszkiewicz, A. Hołda i P. Zajdel, którzy
opanowali biegle zaawansowane teoretyczne techniki
obliczania struktury elektronowej półprzewodników.
129, 159, 141, 142, 155, 157, 158, 177, 198, 239, 240,
243-245].
Rysunek 9. Wspólna herbata w sali seminaryjnej PSOP. Na
zdjęciu W. Kwiatek (pierwszy od lewej), J. Oleszkiewicz, autor
artykułu, E. Czarnecka-Such, B. Popiołek (sekretarka),
P. Klocek (częściowo widoczny), M. Stankiewicz, M. ZimnalStarnawska, J. Konior i R. Samson i A. Banaś.
Rysunek 8. Spotkanie towarzyskie w domu M. ZimnalStarnawskiej. Od lewej M. Podgórny, M. Czyżyk,
F. Antonangeli i autor artykułu.
W latach dziewięćdziesiątych ubiegłego wieku PSOP
poniosła dotkliwe straty szczególnie wśród kolegów
teoretyków. M. Podgórny bezpośrednio po habilitacji,
oraz współpracujący z PSOP R. Markowski, zaraz po
doktoracie, ulegli fascynacji niezwykłym rozwojem
informatyki w USA i wyjechali tam na wieloletnie
kontrakty, z których już nie wrócili do Polski. M.T.
Czyżyk, z podobnych motywów, pozostał na stałe
w Holandii. Poniesiony uszczerbek w gronie teoretyków
w PSOP został częściowo uzupełniony przez Jerzego
Koniora, wychowanka Zakładu Fizyki Statystycznej IF
UJ i adiunkta w Instytucie Fizyki Wyższej Szkoły
Pedagogicznej (obecnie Uniwersytetu) w Rzeszowie.
Do roku 1989 głównym przedmiotem badań
J. Koniora była mikroskopowa teoria płynów prostych,
a badania prowadził we współpracy z prof. Czesławem
Jędrzejkiem z IF UJ [134, 148]. Jeszcze przed powrotem
do IF UJ w 1989 roku J. Konior rozpoczął badania
teoretyczne w zakresie nadprzewodnictwa wysokotemperaturowego [135, 174, 191, 193, 209]. Badania te
kontynuował m.in. podczas pobytu we Francji
w Uniwersytecie Paris-Nord [149, 163, 164, 166, 210]
oraz we współpracy z doktorantem P. Piekarzem [252,
258].
Za wkład do teorii układów silnie skorelowanych
i nadprzewodnictwa wysokotemperaturowego został
nagrodzony Nagrodą Ministra Edukacji Narodowej13.
Niedługo po zatrudnieniu w PSOP ZFO ukończył
rozprawę habilitacyjną [238] i włączył się aktywnie do
prowadzonych w PSOP teoretycznych badań struktury
elektronowej półprzewodników [211]. Wspólnie
z
eksperymentatorami
interpretował
wyniki
doświadczalne
fundamentalnego
odbicia
oraz
absorpcyjnej spektroskopii rentgenowskiej XANES
i EXAFS [201, 214, 225, 264, 268, 269]. Poniesione
straty personalne kompensowało również ponowne
nawiązanie kilkuletniej współpracy „na odległość”
z dr P.M. Lee teoretykiem z Uniwersytetu w Lancaster,
dawnym współpracownikiem autora artykułu. Dzięki
rozwojowi internetu współpraca ta zaowocowała
wieloma wspólnymi wartościowymi publikacjami [128,
Udział PSOP w badaniach z użyciem promieniowania
synchrotronowego
Złożona wiosną 1971 roku przez prof. F. Bassaniego
autorowi artykułu propozycja podjęcia współpracy
polsko-włoskiej w zakresie wykorzystywania do badań
w
spektroskopii
optycznej
półprzewodników
promieniowania synchrotronowego z 1,1 GeV
synchrotronu usytuowanego w Frascati była nadzwyczaj
cenna i dalekowzroczna. Proponowane badania
rozszerzały horyzonty i istotnie modyfikowały programy
badawcze PSOP. Jednakże doprowadzenie do faktycznej
współpracy wymagało jeszcze szeregu ustaleń oraz kilku
lat zabiegów organizacyjnych.
W czasie kolejnej wizyty autora artykułu w Instytucie
Fizyki Uniwersytetu Rzymskiego
w roku 1972
i rewizytach w Krakowie w roku 1973 profesorów
F. Bassaniego i G. Chiarottiego oraz dr A. Balzarottiego,
został sformułowany na piśmie plan wspólnych badań,
dotyczący analizy własności optycznych różnych
związków półprzewodnikowych z użyciem promieniowania synchrotronowego.
Plan ten przewidywał następujący podział zadań: ze
strony polskiej: a) proponowanie tematyki z zakresu
badania
struktury
elektronowej
związków
półprzewodnikowych, b) dostarczanie we współpracy
z Instytutem Fizyki PAN w Warszawie wysokiej jakości
monokrystalicznych związków półprzewodnikowych, c)
prowadzenie komplementarnych badań współczynników
odbicia i pochłaniania światła w zakresie energii
promieniowania od 1,5 do 10,0 eV14, oraz d) częściowe
wsparcie
teoretycznymi
obliczeniami
struktury
elektronowej związków półprzewodnikowych;
ze strony włoskiej: a) współpracę w ramach grupy
Solidi
Roma
przez
udostępnienie
polskim
współpracownikom czasu pracy na próżniowym
spektrometrze wykorzystującym jako źródło światła
promieniowanie
synchrotronu elektronowego we
Frascati w zakresie energii światła od 10 do 300 eV oraz
b) współpracę w zakresie obliczeń teoretycznych
struktury elektronowej związków półprzewodnikowych.
66
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
Opracowany przez PSOP ZFO i grupę Solidi Roma
szczegółowy program badań w zakresie spektroskopii
optycznej
ciała
stałego
z
wykorzystaniem
promieniowania synchrotronowego był pierwszą tego
typu inicjatywą w Polsce.
Ściślejsze kontakty badawcze PSOP z grupą Solidi
Roma nabrały tempa na przełomie roku 1974 i 1975, gdy
na zaproszenie LNF we Frascati i CNR (Centro
Nazionale delle Ricerche) autor artykułu, jako visiting
profesor, wziął udział w badaniach mechanizmu
anomalnie wysokiej absorpcji atomowego wodoru
w palladzie. Badania spektroskopowe własności układu
Pd/H w dalekim próżniowym nadfiolecie miały
rozstrzygnąć o mechanizmie tego anomalnego
pochłaniania.
Niestety, w trakcie badań 1,1 GeV synchrotron uległ
nieodwracalnemu uszkodzeniu i został zdemontowany.
Cząstkowe rezultaty badań przerwanych awarią
synchrotronu zostały zebrane i opublikowane wspólnie
z członkami grupy Solidi Roma w roku 1977 [24,28,29].
W roku 1975 jeszcze przed likwidacją 1,1 GeV
synchrotronu elektronowego we Frascati, grupa Solidi
Roma rozpoczęła, intensywne prace nad wykorzystaniem
promieniowania synchrotronowego z 1,5 GeV
elektronowego pierścienia akumulującego ADONE,
usytuowanego w Narodowym Laboratorium we Frascati
(LNF).
Przystąpiono wówczas do budowy laboratorium
synchrotronowego oraz do projektowania i konstrukcji
kilku nowych linii pomiarowych wykorzystujących
ADONE jako źródło światła.
Działania te koordynował prof. F. Bassani w ramach
powstałego
wówczas
programu
użytkowania
promieniowania synchrotronowego PULS (Programma
per l’Utilizazione della Luce di Sincrotrone).
W realizację programu włączyła się również poszerzona
grupa Solidi Roma. Do współpracy programowej
zaproszono także współpracowników z PSOP. Dyrekcja
Instytutu Fizyki i administracja centralna UJ intensywnie
wspierała wszelkie zabiegi umożliwiające rozwój
współpracy PSOP ZFO z grupą Solidi Roma.
Rysunek 11. Optyczne linie pomiarowe przy 1,1 GeV
synchrotronie: monochromator Mc Pherson na zakres 100 –
500 eV (po lewej) i monochromator Hilger & Watts na zakres
10 – 50 eV. Prof. E.Burattini ustawia monochromator Mc
Phersona.
Starania te, opisane szczegółowiej w Kalendarium
aktywności Instytutu Fizyki I władz Uniwersytetu
Jagiellońskiego
w
staraniach
o
dostęp
i
o
wykorzystywanie
źródeł
promieniowania
synchrotronowego
w
pracach
badawczych15,
doprowadziły do zawarcia w roku 1979 umowy
o współpracy bezpośredniej normującej realną,
wieloletnią,
obustronną
współpracę
pomiędzy
Instytutami Fizyki Uniwersytetu Jagiellońskiego
i Uniwersytetu Rzymskiego I „La Sapienza”.
Szczególne zasługi w tych staraniach mieli prof.
F. Bassani, kierujący grupą Solidi Roma i równocześnie
dyrektor Programu PULS oraz profesorowie G. Chiarotti
i A. Balzarotti. F. Bassani w czasie wizyty w Instytucie
Fizyki UJ w grudniu 1975 roku, na spotkaniu z Rektorem
UJ prof. M. Karasiem zaproponował oficjalną
współpracę PSOP ZFO z programem PULS we Frascati.
Chęć
podjęcia
współpracy
została
oficjalnie
potwierdzona przez Rektora UJ kilka dni po wyjeździe
prof. F. Bassaniego. stosownym listem intencyjnym do
prezydenta INFN.
Rysunek 12. Kopuła budynku pierścienia akumulacyjnego
ADONE w Narodowym Laboratorium we Frascati.
W oparciu o te uzgodnienia, z początkiem roku 1976
profesorowie F. Bassanii i G. Chiarotti wystąpili
równocześnie, przez CNR do Polskiej Akademii Nauk
i przez Ministerstwo Szkolnictwa Wyższego Republiki
Włoskiej do Polskiego Ministerstwa Szkolnictwa
Wyższego i Nauki, o zawarcie porozumień o współpracy
Instytutu Fizyki UJ z programem PULS w zakresie
badań naukowych z użyciem promieniowania do Polskiej
Rysunek 10. Pierścień 1.1GeV synchrotronu elektronowego we
Frascati.
67
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
w aneksie programu badań zostali Prof. F. Bassani oraz
autor artykułu. Umowa ta, zawarta w celu realizacji
bardzo
specjalistycznie
potraktowanych
zadań
badawczych w fizyce ciała stałego, została w latach
następnych rozszerzona na współpracę bezpośrednią
obydwu uniwersytetów w kilku innych dziedzinach
naukowych. Po zawarciu umowy o współpracy
bezpośredniej pomiędzy Uniwersytetami Jagiellońskim
i Rzymskim w roku 1979, otworzyły się przed PSOP
zupełnie nowe możliwości eksperymentalne. W ramach
programu PULS - ADONE była na ukończeniu budowa
czterech linii eksperymentalnych w tym dwu linii
absorpcyjnej spektroskopii rentgenowskiej (XAS) tzn.
linii na zakres energii 2 – 6 keV – zwana linią PULS
i linii rentgenowskiej PWA (Progetto Wiggler Adone) na
twardsze promieniowanie rentgenowskie w zakresie
energii 4,5 – do 25 keV, linii spektroskopii optycznej
w próżniowym nadfiolecie od 6 do 30 eV oraz linii
spektroskopii fotoelektronowej (PES). Jako pierwsza,
została uruchomiona w roku 1979 linia PULS a następnie
linia PWA. Obydwie linie miały służyć do badań
lokalnej struktury kryształów metodą EXAFS (Extended
X-ray Absorption Fine Structure) i do analizy struktury
przykrawędziowej krawędzi rentgenowskich XANES
(X-ray Absorption Near Edge Structure), umożliwiającej
badanie struktury elektronowej pasma przewodnictwa
ciał stałych. Również na linii pomiarowej do badań
optycznych w próżniowym nadfiolecie trwały ostatnie
prace nad jej uruchomieniem. W tej tak bardzo
korzystnej
sytuacji,
została
podjęta
decyzja
o wykorzystaniu do badań materiałów półprzewodnikowych najpierw dwu wyżej wymienionych linii
rentgenowskich a następnie linii optycznej na zakres
próżniowego nadfioletu. Zgłoszony przez nas projekt
dotyczący
analizy
struktury
krystalicznej
w
półprzewodnikowych
związkach
potrójnych
Cd1-xMnxTe dla różnej zawartości Mn z zastosowaniem
metody EXAFS został zaakceptowany i wszedł do
realizacji w roku 1980. Podjęty program badawczy był
nowy i bardzo atrakcyjny naukowo również ze względu
na oczekiwaną możliwość łączenia w związkach
CdMnTe własności materiałów półprzewodnikowych
i magnetycznych. Stwarzało to zapowiedź bardzo
obiecujących aplikacji tego typu związków, nazywanych
półprzewodnikami półmagnetycznymi lub bardziej
poprawnie
półprzewodnikami
z
rozcieńczonym
magnetyzmem. Materiały te były badane dotychczas w
PSOP metodą fundamentalnego odbicia w zakresie
energii promieniowania widzialnego i bliskiego
nadfioletu. Instytut Fizyki PAN w Warszawie wytwarzał
wysokiej jakości monokryształy tych związków oraz
prowadził bardzo szeroki front badań własności
strukturalnych, elektrycznych i magnetycznych. Nasza
propozycja przeprowadzenia komplementarnych badań
opisania lokalnej struktury krystalicznej przy użyciu
analizy EXAFS, dostępnej tylko z zastosowaniem
promieniowania synchrotronowego oraz własności
optycznych w szerokim zakresie energii światła
służących poznaniu struktury elektronowej, została
przyjęta z zadowoleniem zarówno w Instytucie Fizyki
PAN jak i w programie PULS. Eksperymentalna analiza
EXAFS wykonana przez grupę włosko-polską16 na
Akademii Nauk i przez Ministerstwo Szkolnictwa
Wyższego
Republiki
Włoskiej
do
Polskiego
Ministerstwa Szkolnictwa Wyższego i Nauki, o zawarcie
porozumień o współpracy Instytutu Fizyki UJ
z programem PULS w zakresie badań naukowych
z użyciem promieniowania synchrotronowego.
Rysunek. 13. Pierścień akumulujący ADONE.
Podstawą porozumień o współpracy był program
badań przygotowany w PSOP ZFO w roku 1973. Przy
dużej przychylności władz rektorskich obydwu
uniwersytetów, a w szczególności Prorektora UJ Prof.
Alojzego Gołębiewskiego, przez dwa lata poprzedzające
podpisanie umowy o współpracy bezpośredniej
pomiędzy Uniwersytetem Rzymskim La Sapienza
i Uniwersytetem Jagiellońskim trwała regularna
wymiana współpracowników polskich i włoskich.
Wymiana ta zapoczątkowała blisko trzydziestoletnią
ścisłą współpracę IF UJ w programach zastosowania
promieniowania synchrotronowego w fizycznych
i chemicznych badaniach naukowych.
Rysunek 14. Prof. M. Piacentini (od prawej) A. Balzarotti w
gabinecie autora artykułu.
W październiku 1979 r. została podpisana
w Krakowie przez Rektorów Mieczysława Hessa
i Antonio Ruberti’ego formalna umowa o współpracy
bezpośredniej
pomiędzy
uniwersytetami,
która
przewidywała wspólne badania Instytutów Fizyki
obydwu uczelni dotyczące fizyki ciała stałego,
w
zakresie
użytkowania
promieniowania
synchrotronowego w ramach
programu PULS.
Odpowiedzialnymi za poprawną realizację dołączonego
68
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
próbkach Cd1-xMnxTe, została zaprezentowana w trakcie
International Conference on EXAFS and Near Edge
Structure we Frascati we wrześniu 1982, a następnie w
październiku tego roku, jako komunikat na Zjeździe
Włoskiego Towarzystwa Fizycznego w Perugii [64].
głównie informacji o splocie gęstości stanów pasm
walencyjnego i przewodnictwa (funkcja łącznej gęstości
stanów).
Natomiast
spektroskopia
emisji
fotoelektronowej i analiza XANES dostarczają
informacji odpowiednio o gęstości stanów pasma
walencyjnego i pasma przewodnictwa. Mając
możliwości badania fundamentalnego odbicia światła
i równocześnie szeroki dostęp do analizy XANES można
było znacznie wzbogacić wiedzę o strukturze
elektronowej badanych półprzewodników.
Rysunek 15. Autor artykułu (tyłem) i dr A. Savoya przy
optycznej linni pomiarowej PULS w ADONE (1980)
Pewnej dozy adrenaliny dostarczyła świadomość, że
na konferencji we Frascati amerykanie J.C. Mikkelsen
i J.B. Boyce zaprezentowali bardzo podobne wyniki
doświadczalne
dla
potrójnych
związków
półprzewodnikowych
In1-xGaxSb.
W
obydwu
przypadkach brak było odpowiedniej interpretacji
odkrytych, ale niezupełnie zrozumiałych cech badanych
materiałów. Aby możliwie szybko znaleźć właściwe
wyjaśnienie przeprowadzonego eksperymentu zespół
polsko-włoski został wzmocniony przez M. Podgórnego
i M. Czyżyka, kończących właśnie staże teoretyczne
w Dortmundzie. Ich pomysłowość i przygotowanie
teoretyczne spowodowały przełom w interpretacji
wyników doświadczalnych. Grupa amerykańska
opublikowała wyniki badań w the Physical Review
w roku 1983, jednakże z interpretacją budzącą poważne
wątpliwości17.
Nasze
wyniki
doświadczalne
opublikowaliśmy w tym samym czasopiśmie, kilka
miesięcy później, z poprawnym modelowym opisem
lokalnej struktury krystalicznej sfalerytu [77, 78, 100].
Wprowadzony przez nas model, później nazwany
w literaturze modelem sztywnych kationów, wszedł na
trwałe do analizy struktury lokalnej związków
potrójnych o strukturze sfalerytu. Wspólnie z grupą
włoską przeprowadziliśmy badania jeszcze dla kilku
innych związków potrójnych stosując z powodzeniem
ten model w interpretacji wyników [64,70,77-80,96102,104-107]. Wyniki te zostały zauważone nie tylko
w światowej literaturze specjalistycznej. Polscy
członkowie zespołu zostali wyróżnieni Zespołową
Nagrodą Ministra II stopnia (1986)18 a ponadto autor
artykułu otrzymał w roku 1989 Nagrodę Sekretarza
Naukowego PAN19.
Uruchomienie linii rentgenowskiej spektroskopii
absorpcyjnej PWA na zakres energii 4 – 25 keV znacznie
poszerzyło zakres badań struktury lokalnej w związkach
półprzewodnikowych. Analiza XANES i spektroskopia
emisji fotoelektronowej (PES) mogą być metodami
komplementarnymi do analizy fundamentalnego odbicia
ciał stałych. Fundamentalne odbicie światła dostarcza
Rysunek 16. Magnes Wigglera na rentgenowskiej linii PWA w
ADONE
W roku 1983 PSOP uzyskała dostęp do
synchrotronowej optycznej linii pomiarowej w zakresie
próżniowego nadfioletu (6 – 25 eV). Na tej linii zostały
przeprowadzone badania przejść rdzeniowych ze stanów
d w fundamentalnym odbiciu monokrystalicznych
związków ZnTe, CdTe i HgTe, opublikowane w roku
1986 [108,110]. Badania te zapoczątkowały wieloletnią
owocną polsko-włoską współpracę w zakresie
spektroskopii optycznej półprzewodników, w której
widmo fundamentalnego odbicia półprzewodników
i metali było mierzone w Krakowie w zakresie 1,5 – 6
eV, a w zakresie od 6 – 30 eV na linii optycznej
z
użyciem
promieniowania
synchrotronowego
z pierścienia kumulującego ADONE we Frascati [122,
124, 170, 175, 179, 182, 185, 187, 188, 190, 196, 199,
203, 205, 206, 221, 241]. Teoretyczną interpretację
wyników doświadczalnych opracowywali koledzy
z grupy teoretycznej PSOP.
Współpraca pomiędzy PSOP i programami PULS
oraz PWA trwały nieprzerwanie aż do roku 1994, gdy
zakończył pracę pierścień kumulujący ADONE. Zebrana,
w ostatnich miesiącach przed zakończeniem pracy
ADONE, bardzo duża liczba wyników doświadczalnych
dotyczących widm współczynnika odbicia światła
w zakresie energii od 6 – 25 eV oraz krawędzi
rentgenowskich (analiza XANES) dla szeregu
monokryształów związków potrójnych, siarczków
i selenków cynku z wszystkimi metalami przejściowymi,
przygotowanych i dostarczonych głównie przez
W. Giriata, były opracowywane przez nas jeszcze przez
kilka lat po zamknięciu i demontażu ADONE. Po
zakończeniu pracy ADONE współpraca ZFO (Zakład
Fizyki Ogólnej) z wyżej wymienionymi uniwersytetami
włoskimi weszła w nową fazę. Uprzednio zawarte
umowy
o
współpracy
bezpośredniej
zostały
wykorzystane do wspólnych badań, w zakresie
69
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
E. Szeregija przy użyciu konwencjonalnych źródeł
światła o badania przeprowadzone we Frascati z użyciem
promieniowania
synchrotronowego
z
DAΦNE.
Wykorzystanie linii pomiarowej FIR z DAΦNE było
możliwe dzięki posiadanym przez PSOP ważnym
umowom o współpracy bezpośredniej z Uniwersytetami
Rzymskimi La Sapienza i Tor Vergata oraz posiadanemu
przez LNF porozumieniu z Unią Europejską
o współpracy naukowej. Uzyskane pełne wyniki
eksperymentalne częstości i natężeń wzbudzeń
fononowych dały możliwość przeprowadzenia badań
preferencji obsadzeń jonów w potrójnych i poczwórnych
roztworów stałych związków półprzewodnikowych
grupy II – VI. Oczekiwane preferencje obsadzeń jonów
zostały potwierdzone w odpowiednich natężeniach
drgań
fononowych
badanych
związków
półprzewodnikowych [260, 265, 266].
Warto na końcu tego rozdziału ocenić efektywność
współpracy polsko-włoskiej pomiędzy Instytutem Fizyki
UJ i Instytutami Fizyki Uniwersytetów w Rzymie
i w Trento oraz grupą Solidi Roma i programem PULS
na tle stanu badań naukowych prowadzonych z użyciem
promieniowania synchrotronowego przez Polaków
afiliowanych w Polsce. Ta ocena została oparta na spisie
publikacji i dysertacji wykonanych przy użyciu
promieniowania synchrotronowego przez polskich
autorów afiliowanych w polskich instytucjach
naukowych, zamieszczonym w internecie przez Polskie
Towarzystwo
Promieniowania
Synchrotronowego
(PTPS)20. Spis ten informuje, że najwcześniejsze
publikacje z udziałem Polaków pochodziły z roku 1977.
Dotyczyły one przygotowywania w Narodowym
Instytucie Fizyki Jądrowej (INFN) we Frascati cienkich
warstw Pt nasycanych wodorem, przeznaczonych do
badań optycznych w próżniowym nadfiolecie z użyciem
promieniowania synchrotronowego z 1,1 GeV
synchrotronu [24, 28, 29]. Publikacje te były rezultatem,
omawianej powyżej, współpracy Instytutów Fizyki
Uniwersytetu
Jagiellońskiego
i
Uniwersytetu
Rzymskiego I „La Sapienza”, zapoczątkowanej przez te
instytucje w pierwszej połowie lat siedemdziesiątych
ubiegłego wieku. Według spisu PTPS w dziesięcioleciu
1977 – 86 ukazały się 34 publikacje z udziałem polskich
autorów afiliowanych w Polsce. Autorzy reprezentowali:
Instytuty
Fizyki
Uniwersytetu
Warszawskiego,
Politechniki
Warszawskiej
i
Uniwersytetu
Jagiellońskiego oraz Instytut Fizyki PAN w Warszawie
i Instytut Fizyki Jądrowej w Krakowie. Wśród tych
publikacji aż 21 artykułów było wynikiem współpracy
IF UJ z Uniwersytetem Rzymskim I i grupą Solidi Roma.
Stanowiło to 68% całej aktywności Polaków
w dziesięcioleciu 1977 – 1986. W następnym pięcioleciu
(1987 – 1991) aktywność naukowa polskich
użytkowników
promieniowania
synchrotronowego
znacznie wzrosła. Podjęli współpracę kolejni badacze
i instytuty naukowe. W tym okresie opublikowano 85
artykułów, z czego blisko 25% (22 publikacje) było
wynikiem współpracy polsko-włoskiej pomiędzy IF
Uniwersytetu Jagiellońskiego a IF Uniwersytetu
Rzymskiego i IF Uniwersytetu w Trento oraz programem
PULS. Przytoczone zestawienie aktywności naukowej
PSOP IF UJ w porównaniu z piętnastoletnim
modulacyjnej analizy fotoakustycznej [220, 242] i emisji
fotoelektronowej dla binarnych i potrójnych związków
półprzewodnikowych z żelazem [202, 207, 216]. Badania
emisji fotoelektronowej zostały wykonane we
współpracy trójstronnej z Winsconsin Synchrotron
Radiation Centre (USA). W tym okresie były również
kontynuowane badania rentgenowskie metodą XANES
korzystając z pierścienia kumulującego BESSY I
w Berlinie [208, 222] i nowo powstałego pierścienia
kumulującego ELETTRA w Trieście.
Bilansem doskonale układającej się przez wiele lat
współpracy PSOP z grupą Solidi Roma oraz
z programami PULS i PWA były znaczące wyniki
badawcze w zakresie opisanej powyżej rentgenowskiej
analizy EXAFS i XANES, a także liczne rezultaty
eksperymentalne w zakresie spektroskopii optycznej od
bliskiej podczerwieni do zakresu dalekiego próżniowego
nadfioletu. Wyniki te poparte naszymi zaawansowanymi
obliczeniami teoretycznymi dostarczyły ważnych
informacji
o
strukturze
elektronowej
pasma
walencyjnego i przewodnictwa wielu badanych
podwójnych i potrójnych związków półprzewodnikowych oraz związków potrójnych z metalami
przejściowymi. Bezpośrednim rezultatem współpracy
było ponad 80 publikacji w czasopismach o cyrkulacji
międzynarodowej i czynny udział w wielu konferencjach
międzynarodowych.
Od roku 1995 w hali po zdemontowanym pierścieniu
kumulującym ADONE powstawał w LNF nowy
zderzacz (colider) elektronowo-pozytronowy DAΦNE
o energii elektronów i pozytronów 0,7 GeV i unikalnie
silnym prądzie elektronów i pozytronów (do ok. 2 A)
poruszających się w pierścieniu przeciwbieżnie.
Wyprowadzane z tego pierścienia promieniowanie
synchrotronowe ma kilkakrotnie wyższe natężenie
w porównaniu z innymi pierścieniami kumulującymi.
Charakterystyka
spektralna
promieniowania
synchrotronowego z DAΦNE, umożliwiła budowę linii
pomiarowej do badań absorpcyjnej i emisyjnej
spektroskopii rentgenowskiej w zakresie energii od 1,5 4 keV oraz linię spektroskopii optycznej w zakresie
dalekiej
podczerwieni
począwszy
od
energii
kilkudziesięciu cm-1 (FIR). W tym obszarze widmowym
są
obserwowane
wzbudzenia
fononowe
charakterystyczne dla krystalicznej struktury lokalnej ciał
stałych. Z tego względu wyniki analizy wzbudzeń
fononowych mogły być konfrontowane z wynikami
badań struktury lokalnej kryształów otrzymanymi przy
użyciu analizy EXAFS. Prowadzona przez PSOP we
współpracy z dr V Robouchem z LNF we Frascati
pogłębiona analiza wyników EXAFS wykazała
preferencje obsadzeń jonów w potrójnych i poczwórnych
roztworach związków półprzewodnikowych [225, 238,
246, 250, 261, 268, 269]. W celu potwierdzenia
komplementarności badań struktury lokalnej kryształów
przy użyciu analizy EXAFS z badaniami częstości
wzbudzeń fononowych kryształów w obszarze dalekiej
podczerwieni, PSOP nawiązał współpracę z grupą prof.
Eugeniusza Szeregija z Instytutu Fizyki Wyższej Szkoły
Pedagogicznej w Rzeszowie (obecnie Uniwersytet
Rzeszowski). Nawiązana współpraca umożliwiła
rozszerzenie badań prowadzonych przez grupę prof.
70
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
ogólnopolskim
użytkowaniem
promieniowania
synchrotronowego w badaniach naukowych, uzmysławia
celowość organizowanej konsekwentnie przez Instytut
Fizyki Uniwersytetu Jagiellońskiego, od pierwszej
połowy lat siedemdziesiątych ubiegłego stulecia, ścisłej
współpracy
polsko-włoskiej
ukierunkowanej
na
stosowanie promieniowania synchrotronowego w fizyce
ciała stałego.
Współpraca
PSOP
z
Polskim
Promieniowania Synchrotronowego
międzynarodowych szkół i sympozjów oraz sympozjów
krajowych.
Towarzystwem
Wraz z coraz bardziej intensywnym rozwojem badań
z użyciem promieniowania synchrotronowego w latach
osiemdziesiątych ubiegłego stulecia, fizycy i chemicy
oraz współpracujący z nimi lekarze i biologowie zaczęli
wyrażać potrzebę integracji polskiego środowiska
naukowego, pracującego przy różnych źródłach
promieniowania
synchrotronowego.
Wychodząc
naprzeciw temu zapotrzebowaniu PSOP ZFO
prowadząca
intensywne
badania
z
użyciem
promieniowania
synchrotronowego
w
zakresie
absorpcyjnej spektroskopii rentgenowskiej i spektroskopii optycznej półprzewodników, podjęła się wspólnie
z Instytutem Fizyki PAN w Warszawie organizacji
pierwszego Sympozjum Użytkowników Promieniowania
Synchrotronowego.
W lutym 1991 roku z inicjatywy i staraniem
profesora Juliana Auleytnera oraz autora artykułu,
odbyło się w Uniwersytecie Jagiellońskim, w pałacyku
Szyszko-Bohusza I Krajowe Sympozjum Użytkowników
Promieniowania Synchrotronowego. Na Sympozjum
wygłoszono 25 piętnastominutowych komunikatów
z badań prowadzonych przez polskich badaczy przy
użyciu promieniowania synchrotronowego. Uczestnicy
Sympozjum zadeklarowali chęć utworzenia Polskiego
Towarzystwa
Promieniowania
Synchrotronowego
(PTPS). Wśród 28 członków założycieli było dwunastu
z Instytutu Fizyki i Chemii UJ, w tym osiem osób
z PSOP ZFO. Pozostali reprezentowali Instytut Fizyki
PAN w Warszawie, Uniwersytet Warszawski i kilka
innych ośrodków. W maju 1991 r. Towarzystwo zostało
zarejestrowane z siedzibą w Instytucie Fizyki UJ
i rozpoczęło działalność integracyjną i edukacyjną
powstającego
środowiska
naukowego
poprzez
organizację międzynarodowych szkół i sympozjów.
PSOP ZFO włączyło się bardzo aktywnie do działalności
w PTPS organizując Drugie Krajowe Sympozjum
Użytkowników Promieniowania Synchrotronowego
w Mogilanach (1993) i Czwarte Krajowe Sympozjum
w Domu Polonijnym Uniwersytetu Jagiellońskiego
w Przegorzałach (1997) oraz uczestniczyło czynnie we
wszystkich inicjatywach PTPS. Szczegóły tej
działalności zostały przedstawione
w Kalendarium
starań Instytutu Fizyki (notka 14) oraz Kalendarium
starań
Polskiego
Towarzystwa
Promieniowania
Synchrotronowego o dostęp do europejskich źródeł
promieniowania synchrotronowego21. Zapraszanie wielu
wybitnych specjalistów z ośrodków synchrotronowych
na organizowane przez PTPS i odbywające się regularnie
międzynarodowe sympozja i szkoły ułatwiało
nawiązywanie kontaktów i tworzenie owocnej
współpracy
przez
polskich
uczestników
Rysunek 17. Uczestnicy 1-szej Międzynarodowej Szkoły
i Sympozjum Promieniowania Synchrotronowegow Naukach
Przyrodniczych (1992). W pierwszym rzędzie stoją
profesorowie B. Orłowski, I. Sosnowska, autor artykułu,
J. Auleitner, G. Margaritondo, M. Antonetti oraz K. Jabłońska.
W dalszych rzędach m. in. W. Wierzchowski, J. Haertwig,
E. Sobczak, W. Kwiatek, R. Haensel, J. Nordgren,
C. Malgrange, A. Kvick
Uwagi końcowe
Po przejściu autora artykułu na emeryturę w roku
2002, Zakład Fizyki Ogólnej i Pracownie należące do
Zakładu zostały rozwiązane. Personel Zakładu został
włączony do Zakładu Fizyki Doświadczalnej, z którego
ZFO wyodrębnił się w roku 1970. W trzydziestodwuletniej działalności naukowej ZFO były prowadzone
intensywne
badania
naukowe
w
niełatwej
eksperymentalnie
spektroskopii
interferencyjnej,
spektroskopii optycznej półprzewodników, absorpcyjnej
spektroskopii rentgenowskiej, spektroskopii fotoemisji
elektronowej, spektroskopii fononowej i spektroskopii
molekularnej. Uzyskane wyniki badań były zauważane
przez specjalistów. Opublikowano około 270 artykułów
i komunikatów w większości w czasopismach
o cyrkulacji międzynarodowej. W ZFO doktoryzowało
się 15 asystentów i doktorantów22 a 4 osoby habilitowały
się23. Szereg prac doktorskich zostało nagrodzonych
Nagrodami Indywidualnymi III stopnia Ministra Nauki,
Szkolnictwa Wyższego i Techniki. W chwili rozwiązania
ZFO liczył 9 pracowników: dwu doktorów
habilitowanych J. Koniora i M. Stankiewicza, czterech
starszych wykładowców: R. Kloch, B. Pukowską,
J. Szczeklika i M. Zimnal-Starnawską, dwu
samodzielnych fizyków: E. Czarnecką-Such i J.
Olejniczaka oraz starszego elektronika R. Samsona.
Doktorzy habilitowani J. Konior i M. Stankiewicz
otrzymali tytuły profesora w roku 2009. Prof. J. Konior
należy
obecnie
do
Zakładu
Nanostruktur
i Nanotechnologii, a prof. M. Stankiewicz jest
dyrektorem Narodowego Centrum Promieniowania
Synchrotronowego Solaris, w którym od wiosny
bieżącego roku trwa rozruch pierwszego polskiego
synchrotronu SOLARIS. Będzie on służyć jako źródło
promieniowania synchrotronowego przeznaczone do
badań w naukach przyrodniczych. Zbudowane źródło
promieniowania synchrotronowego jest wielką szansą
71
Synchrotron Radiation in Natural Science Vol. 14, No. 1-2 (2015)
i jednocześnie wyzwaniem dla przyszłych użytkowników
promieniowania synchrotronowego w Polsce.
Po rozwiązaniu ZFO niektórzy pracownicy
przeniesieni do ZFD kontynuowali działalność naukową
rozwijaną w PSOP. J. Konior prowadził badania
teoretyczne analizy XANES dla struktury elektronowej
siarki w siarczkach metali przejściowych i w komórkach
rakowych prostaty [270, 271, 274-276] a B. Pukowska
analizowała metodami spektroskopii optycznej dyfuzję
defektów w związkach CdHgTe i wpływ oczyszczania
CdTe wodorem na jego fundamentalne odbicie światła
[272, 273]. M. Zimnal-Starnawska w roku 2008
uczestniczyła w serii badań XANES na linii
rentgenowskiej zderzacza elektronowo pozytronowego
DAΦNE w Frascati.
12
13
14
Podziękowanie
15
Autor bardzo dziękuje dawnym współpracowniczkom
dr Marcie Zimnal-Starnawskiej i dr Barbarze
Pukowskiej, za wiele cennych uwag i uzupełnień
wykorzystanych przy pisaniu tego artykułu.
___________________________________________________
1
2
3
4
5
6
7
8
9
10
11
A. Strzałkowski, B. Średniawa, Historia Fizyki
w Uniwersytecie Jagiellońskim, w książce Uniwersytet
Jagielloński, Złota KsięgaWydziału Matematyki i Fizyki,
red. B. Szafirski, Kraków 2000.
A. Kisiel, H. Niewodniczański, A. High Luminosity Quartz
Spectrograph for the Far Ultra Violet Region 2300-1850 A,
Acta Phys. Polon. 17, (1958) 361; A. Kisiel,
H. Niewodniczański, Intensity Ratios in Doublets of the Fine
Structure in the Al III Spectra, Acta Phys. Polon. 20 (1961)
633; A.Kisiel, Intensity Ratios in Doublets of the Fine
Structure in the A1 III and Si IV Spectra, Acta Phys. Polon
23 (1963) 167.
J.C. Phillips, Direct observation of open magnetic orbits,
J. Electronics, 1, 162 (1955); F.C. Jahoda, Fundamental
Absorption of Barium Oxide from its Reflectivity Spectrum,
Phys.Rev., 107 (1958) 1261.
H.R. Philipp, A.E. Taft, Optical Constants of Germanium in
the Region 1 to 10 eV, Phys. Rev., 113 (1959) 1493.
H.R. Philipp, A.E. Taft, Optical Constants of Silicon in the
Region 1 to 10 eV, Phys. Rev., 120 (1960) 37.
A. Kisiel, Intensity Ratios in Doublets of the Fine Structure
in the A1 III and Si IV Spectra, Acta Phys. Polon., 23 (1963)
167.
Spis publikacji Pracowni Spektroskopii Optycznej
Półprzewodników cytowanych w artykule w nawiasach
kwadratowych można znaleźć w internecie pod adresem
http://www.synchrotron.org.pl/publ/biulet/vol14/Kisiel_spis
_publikacji_PSOP.pdf
W skład grupy Solidi Roma wchodzili ze strony Instytutu
Fizyki Uniwersytetu Rzymskiego „La Sapienza”:
F. Bassani, A. Bianconi, G. Chiarotti, i M. Piacentini, a ze
strony Naczelnego Instytutu Zdrowia (Istituto Superiore di
Sanita) E. Burattini, i G. Grandolfo
M. Czyżyk, D. Dębowska i J. Oleszkiewicz
Nagrodę otrzymali A. Kisiel i A. Rodzik
A. Kisiel, B. Pukowska, M. Zimnal-Starnawska, Działalność
Naukowa Zakładu Fizyki Ogólnej Instytutu Fizyki
Uniwersytetu Jagiellońskiego (1970-2002), (2014)
16
17
18
19
20
21
22
23
72
http://www.fais.uj.edu.pl/nauka/o-profesorach-tekstywywiady,
Prof. J. Treutsch po objęciu stanowiska dyrektora
Forschungszentrum w Julich został uhonorowany tytułem
doktora honoris causa Uniwersytetu Jagiellońskiego za
wybitny wkład w teoretyczną fizykę ciała stałego i
organizowanie bardzo efektywnej międzynarodowej
współpracy naukowej a w szczególności wspieranie
aktywne rozwoju wspólnych badań w fizyce jądrowej
Forschungzentrum i Instytutu Fizyki Uniwersytetu
Jagiellońskiego.
Wspólnie z A.M. Olesiem i J. Dutką
Badania w nadfiolecie próżniowym 6 - 10 eV miały być
zrealizowane w Krakowie po zakupie przez IF UJ
1-metrowego próżniowego monochromatora siatkowego
firmy Hilger & Watts i po zbudowaniu odbiciomierza
fotoelektrycznego z odpowiednimi wodorowymi i helowymi
źródłami światła.
A. Kisiel, Kalendarium aktywności Instytutu Fizyki I władz
Uniwersytetu Jagiellońskiego w staraniach o dostęp
i
o
wykorzystywanie
źródeł
promieniowania
synchrotronowego w pracach badawczych, Synchrotron
Radiation in Natural Science, Bulletin of the Polish
Synchrotron Radiation Society, Vol. 12, No. 1-2, 56 – 62
(2013), oraz A. Kisiel, Kalendarium starań Instytutu Fizyki
i władz Uniwersytetu Jagiellońskiego o dostęp
i o wykorzystywanie europejskich źródeł promieniowania
synchrotronowego
w
pracach
badawczych,
http://www.if.uj.edu.pl/documents/3830070/70875255/Kale
ndarium%20IF%20UJ.pdf (2015)
W składzie: F. Antonangeli, A. Balzarotti, N. Motta,
M. Piacentini, A. Kisiel, M. Zimnal-Starnawska,
A. Mycielski i W. Giriat
J.C. Mikkelsen. J. B. Boyce, Phys. Rev., B28 (1983) 7130.
Nagrodzeni zostali M. Czyżyk, A. Kisiel, M. Podgórny
i M. Zimnal-Starnawska
Nagroda za kierowanie zespołem i udział w pracy pt.
„Badanie struktury lokalnej i własności termodynamicznych
roztworów stałych typu A1-xBxC o uporządkowaniu
tetraedrycznym”
Publications and disertations concerning the synchrotron
radiation and its applications, as well as closely related
fields by authors affiliated in Poland, Table IV, Sorted
according to publication year – strona internetowahttp://cluster003.ovh.net/~synchrot/old/July2008-Yearv2.pdf
A. Kisiel, Kalendarium starań Polskiego Towarzystwa
Promieniowania Synchrotronowego w latach 1991 – 2002
o dostęp do europejskich źródeł promieniowania
synchrotronowego, Synchrotron Radiation in Natural
Science, Bulletin of the Polish Synchrotron Radiation
Society, Vol. 12, No. 1-2, 63 - 66 (2013)
Marek Podgórny (1978), Barbara Oleś (1979), Barbara
Pukowska (1979), Marta Zimnal-Starnawska (1980),
Katarzyna Karnicka-Mościcka (1981), Andrzej Rodzik
(1981), Marek Turowski (1982), Józef Oleszkiewicz (1985),
Dorota Dębowska (1992), Jacek Goniakowski (1995), Artur
Hołda (1998), Paweł Zajdel (2003), Agnieszka Banaś (2004)
Marek Podgórny (1991), Jerzy Konior (1998), Marek
Stankiewicz (1998).
ISSRNS 2014: Abstracts / Synchrotron Radiation in Natural Science Vol. 13, No. 1 (2014)
FUTURE CONFERENCES AND WORKSHOPS
conference
web address
date
16th International conference on
Small-Angle Scattering
(Berlin, Germany)
https://www.helmholtz-berlin.de/events/sas/
2015-09-13 2015-09-18
23rd International Congress of
X-ray Optics and Microanalysis
(Upton, US)
http://www.bnl.gov/icxom23/
2015-09-14 2015-09-18
13th School of Synchrotron
Radiation (Grado, Italy)
www.synchrotron-radiation.it
2015-09-14 2015-09-25
23rd Conference of Applied
Crystallography
(Krynica Zdrój, Poland)
http://crystallography.us.edu.pl/
2015-09-20 2015-09-24
2015 IUCr High-Pressure
Workshop (Campinas, Brazil)
http://pages.cnpem.br/hpworkshop/
2015-09-12 2015-09-15
IBIC 2015: International Beam
Instrumentation Conference
(Melbourne, Australia)
http://ibic2015.org/
2015-09-13 2015-09-17
58 Zjazd Naukowy Polskiego
Towarzystwa Chemicznego
(Gdansk, Poland)
http://ptchem2015.ug.edu.pl/pl/
2015-09-21 2015-09-25
8th Medical Applications of
Synchrotron Radiation
(Grenoble, France)
http://www.esrf.eu/masr2015
2015-10-05 2015-10-09
7th Hard X-Ray FEL
Collaboration Meeting
http://indico.psi.ch/conferenceDisplay.py?confId=3409
2015-10-25 2015-10-29
In Situ Serial Crystallography
Workshop
(PSI Villigen, Switzerland)
http://indico.psi.ch/conferenceDisplay.py?confId=3677
2015-11-17 2015-11-19
NMBS workshop: New
Synchrotron Radiation and
Optical Techniques for Nanoscale
Microscopy of Biological
Systems: From Single Molecules
to Cells (Trieste, Italy)
http://www.elettra.eu/Conferences/2015/NMBS/
2015-12-09 2015-12-10
73
ISSRNS 2014: Abstracts / Synchrotron Radiation in Natural Science Vol. 13, No. 1 (2014)
RESONANCE workshop:
Multicolor FEL Pulses and
Coherent Control on the
Attosecond Time Scale Opening
New Science Perspectives
(Trieste, Italy)
http://www.elettra.eu/Conferences/2015/RESONANCE/
2015-12-10 2015-12-11
BioXFEL STC 3rd Annual
International Conference (San
Juan, Puerto Rico)
https://www.bioxfel.org/events/details/64
2016-01-13 2016-01-15
SUM16: 11th SOLEIL Users’
Meeting (SOLEIL, Palaiseau,
France)
http://www.synchrotronsoleil.fr/portal/page/portal/Soleil/ToutesActualites/Workshops/2016
/SUM2016/Accueil
2016-01-21 2016-01-22
DESY Photon Science Users'
Meeting (Hamburg, Germany)
http://photonscience.desy.de/users_area/users%27_meeting/index_eng.html
2016-01-28 2016-01-29
ESRF Users Meeting (Grenoble,
France)
http://www.esrf.eu/home/events/conferences/2016/um2016.html
2016-02-08 2016-02-10
9th Frolic Goats High Pressure
Diffraction Workshop
(Poznan, Poland)
http://frolicgoats.amu.edu.pl/
2016-04-... 2016-04-...
EPDIC15: 15th European Powder
Diffraction Conference
(Bari, Italy)
http://www.ba.ic.cnr.it/epdic15/
2016-06-12 2016-06-15
ECM-30: European
Crystallography Meeting
(Basel, Switzerland)
http://ecm30.ecanews.org/
2016-08-28 2016-09-01
74
ISSRNS 2014: Abstracts / Synchrotron Radiation in Natural Science Vol. 13, No. 1 (2014)
Presenting Author’s Index
W.
Andrzejewska
P-15
51
D.
Paliwoda
O-06
27
M.
Bagińska
P-21
57
W.
Paszkowicz
P-04
37
A.
Bajorek
P-06
39
J.
Pełka
O-07
28
A.
Burian
L-04
8
Z.
Pietralik
P-18
54
J.
Cebulski
L-08
14
P.
Piszora
P-23
59
I.
Demchenko
L-03
5
M.
Pławecki
O-03
22
A.
Drzewiecka-Antonik
L-07
13
R.
Rapacz
P-03
36
E.
Dynowska
P-10
45
J.
Rybka
P-16
52
H.
Fiedorowicz
O-05
23
M.
Sikora
L-11
17
W.
Gawelda
L-09
15
M.
Skupin
P-14
50
P.
Goryl
O-12
33
Cz.
Ślusarczyk
L-06
10
W.
Gospodarczyk
O-10
31
M. A.
Śmiałek
P-17
53
Jacyna
P-09
44
R.
Sobierajski
L-10
16
Kisiel
A-01
61
P.
Solarz
P-05
37
M. T.
Klepka
P-11
46
M.
Stankiewicz
L-14
-
D.
Klinger
P-08
43
P.
Starowicz
O-01
20
Kolodziej
L-13
19
J.
Szlachetko
L-01
1
I.
A.
J. J.
Ż.
Kołodziejska
P-13
49
K.
Szutkowski
P-24
60
M.
Kozak
O-08
28
M.
Taube
O-09
30
M.
Kręcisz
P-16
52
A.
Thissen
S-01
33
M.
Kręglewski
L-12
18
T.
Tyliszczak
L-02
4
J.
Kubacki
O-04
23
V.
Vasylechko
L-05
9
K.
Lawniczak-Jablonska
P-12
47
T. J.
Wasowicz
P-19
54
Y.
Melikhov
O-02
21
M.
Wojdyła
P-22
58
R.
Minikayew
P-02
34
A.
Wolska
P-07
42
R.
Mroczka
O-11
32
P.
Zajdel
P-20, P-21, P-22
56,57,58
B. A.
Orlowski
P-01
34
K.
Żebrowska
P-20
56
75

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