[18p-E216-1~10] 10.4 半導体スピントロニクス・超伝導・強相関

[18p-E216-6] GaAsBi薄膜中の電子におけるKerr回転スペクトロスコピー

〇国橋 要司¹、田中 祐輔¹、眞田 治樹¹、好田 誠²、新田 淳作²、長谷川 将³、西中 浩之³、吉本 昌広³、後藤 秀樹¹ (1.NTT物性研、2.東北大工、3.京都工繊大)

キーワード：GaAsBi、スピン軌道相互作用、Kerr回転

GaAsBi is a candidate material for spintronics applications in terms of spin control via spin-orbit effective magnetic fields because the addition of bismuth atoms to GaAs crystal significantly enhances the spin-splitting energy [1]. However, to date, the research on spin dynamics in such diluted bismide has been limited. Here, we investigate the electron spin dynamics in GaAs_1-xBi_x using Kerr rotation spectroscopy based on a pump-probe technique. A Kerr rotation signal was observed for a wide wavelength region of 840 to 906 nm, where the initial phase of the spin precession under an external magnetic field was changed continuously from 0 to p. This nontrivial dependence of the spin phase on the excitation wavelength implies that the spin properties are influenced by the energy band structures in GaAs_1-xBi_x, and thus our findings are beneficial as regards understanding the spin properties of diluted GaAs_1-xBi_x alloy.