[23p-E205-1~18] 10.4 半導体・トポロジカル・超伝導・強相関スピントロニクス

▲ [23p-E205-7] Optical detection of spin-orbit effective magnetic field in GaAsBi epilayer

〇Yoji Kunihashi¹、Haruki Sanada¹、Yusuke Tanaka¹、Katsuya Oguri¹、Makoto Kohda²、Junsaku Nitta²、Sho Hasegawa³、Hiroyuki Nishinaka³、Masahiro Yoshimoto³、Hideki Gotoh¹ (1.NTT BRL、2.Tohoku Univ.、3.Kyoto Inst. Tech.)

キーワード：spin-orbit interaction, Kerr rotation, GaAsBi

We investigate the strength and direction of spin-orbit effective magnetic fields for diffusive electron spin in a GaAsBi epilayer by Kerr rotation microscopy based on a pump-probe technique. Spatiotemporal mapping of Kerr rotation in a magnetic field revealed the spin precession due to the effective magnetic field during the diffusion process of electrons. We found that the effective magnetic field in the investigated GaAsBi epilayer has a Rashba-type symmetry. This is the first quantitative estimation of effective magnetic fields in GaAs_1-xBi_x, and thus our findings are beneficial for understanding the spin properties of diluted GaAs_1-xBi_x alloy.