10:30 〜 10:45
▲ [18a-D704-6] [The 53rd Young Scientist Presentation Award Speech] The origin of the acoustic spin Hall effect
キーワード:surface acoustic wave, spin current, spin orbit interaction
We demonstrated that SAW induces AC spin current in a heavy metal (HM) via spin-orbit interaction (acoustic spin Hall effect). The microscopic mechanism of the SAW-induced AC spin current, however, remained uncovered. In this work, we aim to identify the underlying mechanism of SAW-induced AC spin current. The acoustic voltages are measured for SAW devices with different SAW propagation orientation with respect to the electric polarization of a ferroelectric substrate. We also model the electromagnetic responses of a metallic thin film to an AC electric field coupled with SAW at the surface of the ferroelectric substrate. Obtained results indicate that the SAW-induced AC spin current is generated from the SAW-induced AC electric field via the spin Hall effect.