Sign of inverse spin Hall voltages generated by ferromagnetic resonance and temperature gradients in yttrium iron garnet platinum bilayers

イットリウム鉄ガーネット(YIG)プラチナ2層膜中の温度勾配と強磁性共鳴

Schreier, M.*; Bauer, G. E. W.*; Vasyuchka, V.*; Flipse, J.*; 内田 健一*; Lotze, J.*; Lauer, V.*; Chumak, A.*; Serga, A.*; 大門 俊介*; 吉川 貴史*; 齊藤 英治; Van Wees, B. J.*; Hillebrands, B.*; Gross, R.*; Goennenwein, S. T. B.*

Schreier, M.*; Bauer, G. E. W.*; Vasyuchka, V.*; Flipse, J.*; Uchida, Kenichi*; Lotze, J.*; Lauer, V.*; Chumak, A.*; Serga, A.*; Daimon, Shunsuke*; Kikkawa, Takashi*; Saito, Eiji; Van Wees, B. J.*; Hillebrands, B.*; Gross, R.*; Goennenwein, S. T. B.*

We carried out a concerted effort to determine the absolute sign of the inverse spin Hall effect voltage generated by spin currents injected into a normal metal. We focus on yttrium iron garnet (YIG)|platinum bilayers at room temperature, generating spin currents by microwaves and temperature gradients. We find consistent results for different samples and measurement setups that agree with theory. We suggest a right-hand-rule to define a positive spin Hall angle corresponding to the voltage expected for the simple case of scattering of free electrons from repulsive Coulomb charges.