Spin-Transfer Torque and Domain Wall Motion in Magnetic

Electric-field Effect on Thin Ferromagnetic Layers
F. Matsukura
Center for Spintronics Integrated Systems, Tohoku University
Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical
Communication, Tohoku University, Sendai 980-8577, Japan
Magnetic properties of (Ga,Mn)As, such as the Curie temperature, coercive force, and
magnetic anisotropy, are a function of the hole concentration, and thus can be controlled by
the application of an electric field to the gate electrode of metal-insulator-semiconductor
(MIS) structures [1-4].
We report on the effect of gating on magnetism in (Ga,Mn)As which can be explained by
the adapted p-d Zener model for thin (Ga,Mn)As layers with a non-uniform hole profile along
the growth direction [5, 6]. We report also on the electric-field effect on the magnetic
anisotropy in thin CoFeB layers sandwiched by Ta and MgO [7].
The work was supported in part by JSPS through its First program and the GCOE program
at Tohoku University.
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