[17p-K102-1~12] 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

14:00 〜 14:15奨励賞エントリー英語発表

[17p-K102-3] Giant Spin-Orbit Torque in a Two-Dimensional Hole Gas at the Surface of Hydrogen-Terminated Diamond

〇Fujio Sako¹, Ryo Ohshima^1,2, Yuichiro Ando³, Naoya Morioka^2,4, Hiroyuki Kawashima⁴, Riku Kawase⁴, Norikazu Mizuochi^2,4, Hans Huebl^5,6,7, Masashi Shiraishi^1,2 (1.Kyoto Univ., 2.CSRN, Kyoto Univ., 3.Osaka Metro. Univ., 4.ICR, Kyoto Univ., 5.W.-Meissner-Inst., 6.Tech. Univ. Munich, 7.Munich CQST)

キーワード：

hydrogen-terminated diamond、two-dimensional hole gas、spin-orbit torque

Two-dimensional hole gas (2DHG) is created at the surface of hydrogen-terminated (H-) diamond, which is a potential platform for charge-to-spin conversion through the Rashba-Edelstein effect. In this study, the charge-to-spin conversion in H-diamond was observed by performing the second harmonic Hall measurement, which is a widely used technique to estimate spin-orbit torque (SOT) efficiency. A Hall-bar shaped H-diamond (001) / Ni₈₀Fe₂₀ (Py) device was prepared, and the SOT efficiency ξ_DL was examined. The Rashba-Edelstein length in the 2DHG λ_REE^2DHG, was estimated as an index of the charge to spin conversion efficiency in 2DHG from by solving the spin diffusion equation, in which the 2DHG is considered as the boundary condition for the bottom of the Py. From the Py thickness dependence of ξ_DL, λ_REE^2DHG was estimated to be comparable to the product of spin Hall angle and spin difusion length of Pt, and inverse Rashba-Edelstein length in LAO/STO, both at room temperature.