[16p-D704-1~18] 10.4 Spintronics in semiconductor, topological material, superconductor, and multiferroics

[16p-D704-4] Quantitative estimation of spin-orbit interaction parameters
in GaAsBi epitaxial film

〇Yoji Kunihashi¹, Yasushi Shinohara¹, Sho Hasegawa², Hiroyuki Nishinaka², Masahiro Yoshimoto², Katsuya Oguri¹, Hideki Gotoh^1,3, Makoto Kohda⁴, Junsaku Nitta^1,4, Haruki Sanada¹ (1.NTT BRL, 2.Kyoto Inst. Tech., 3.Hiroshima Univ., 4.Tohoku Univ.)

Keywords:spin-orbit interaction, Kerr rotation, GaAsBi

The Rashba spin-orbit interaction (SOI) induced by structure inversion asymmetry in III-V semiconductor heterostructures plays an important role in spin manipulation with an external electric field since its strength is electrically controllable via gate bias voltage. Thus, enhancement of the Rashba SOI is one of the key issues for future spintronics devices. Dilute bismides of III-V compound semiconductors are candidate materials for large Rashba SOI because the atoms having large atomic number significantly enhances the intrinsic SOI in III-V semiconductors [1]. However, the quantitative determination of SOI in such dilute bismides has not been reported. We investigated the strength of SOI in a GaAsBi epitaxial layer by Kerr rotation microscopy on the basis of the pump-probe technique. We found that the Rashba SOI parameter alpha is 2.5 meVÅ whereas the Dresselhaus SOI parameter beta induced by bulk inversion asymmetry is much smaller than a in the current GaAsBi heterostructure.