[16p-Z19-1~23] 10.1 新物質・新機能創成（作製・評価技術）

▼ [16p-Z19-5] Observation of breaking of Onsager’s reciprocal relation in a high spin Hall angle ferromagnetic Weyl semimetal at room temperature

〇(D)LIVIO LEIVA¹、Simon Granville²、Yao Zhang²、Sergey Dushenko¹、Teruya Shinjo¹、Ryo Ohshima¹、Yuichiro Ando¹、Masashi Shiraishi¹ (1.Kyoto Univ.、2.Victoria Univ. Well.)

キーワード：heusler alloy, spin hall effect, spintronics

Weyl semimetals are playing a major role in condensed matter physics due to exotic topological properties, and their coexistence with ferromagnetism may lead to enhanced spin-related phenomena. In this work, the inverse spin Hall effect (ISHE) in ferromagnetic Weyl-semimetal Heusler alloy Co₂MnGa was investigated at room temperature by means of electrical spin injection in lateral spin valve structures. The spin Hall angle was found to be as high as -19%, which is among the highest reported for a ferromagnet. Although this value is in the same order of magnitude of known heavy metals, the significantly higher resistivity of Co₂MnGa implies larger detection voltages. In addition, a breaking of Onsager reciprocal relation was systematically observed for the first time in this kind of transport phenomena, and an explanation considering different spin dependent Hall conductivity for spin-up and spin-down carriers is introduced.