Tohoku University. Research Profiles


Electrical Spin Generation and Manipulation in Semiconductors



Since spin orbit interactions caused by the structural inversion asymmetry and the bulk inversion asymmetry induce an effective magnetic field in III-Vsemiconductor heterostructures, it is possible to realize the new functional devices based on the electrical control of the spin precession. We study the electrical spin generation by using spatial modulation of spin orbit interaction, which demonstrates Stern-Gerlach spin filter in semiconductors, and research ultra-fast spin dynamics by using time resolved Kerr rotation microscopy. We also investigate a spin MOSFET based on the perpendicular magnetic materials and electric-field induced magnetization control. We can reduce the leak current and the signal delay in the logic circuit. With the non-volatility of the ferromagnetic source and drain electrodes, random access memory is also enabled by using the spin MOSFET structure.

Targeted Application(s)/Industry

Target application will be low power logic devices and non-volatile memory based on electron spins and also future metal-based spintronic devices.


Department of Materials Science, Graduate School of Engineering

KOHDA Makoto , Professor
Doctor of Engineering


Related Information

1.“Spin orbit induced electronic spin separation in semiconductor nanostructures”,
M. Kohda, S. Nakamura, Y. Nishihara, K. Kobayashi, T. Ono, J. Ohe, Y. Tokura, T. Mineno, and J. Nitta.
Nature Communications 3, 1082 (2012).

2.“Gate-controlled persistent spin helix state in (In,Ga)As quantum wells”,
M. Kohda, V. Lechner, Y. Kunihashi, T. Dollinger, P. Olbrich, C. Schönhuber, I. Caspers, V. V. Bel’kov, L. E. Golub, D. Weiss, K. Richter, J. Nitta, and S. D. Ganichev.
Phys. Rev. B 86, 081306(R)-1 - 081306(R)-4 (2012).

3.“Enhancement of spin orbit interaction and the effect of interface diffusion in InGaAsP/InGaAs heterostructures”,
M. Kohda and J. Nitta,
Phys. Rev. B 81, 115118-1 - 115118-8 (2010).

4.“Manipulating spin orbit interaction in semiconductors”, (Invited Review)
M. Kohda, T. Bergsten, and J. Nitta,
J. Phys. Soc. Japn. 77, 031008 (2008).