[17a-Z19-1~12] 10.2 Fundamental and exploratory device technologies for spin

[17a-Z19-7] Quantitative Amplitude Evaluation of Surface Acoustic Waves using Sagnac

〇Daichi Nishikawa¹, Shoma Tateno¹, Kazuto Yamanoi¹, Makoto Okano¹, Yukio Nozaki¹, Shinichi Watanabe¹ (1.Keio Univ.)

Keywords:spin-vorticity coupling, surface acoustic wave, sagnac interferometer

It has been confirmed that AC spin currents can be generated in a nonmagnetic body using the vorticity of surface acoustic waves (SAWs) by spin-vorticity coupling. In this talk, we describe an optical method to quantitatively evaluate the vertical micro-displacement of SAWs by using an optical probe method with the introduction of a Sagnac interferometer. By perfectly synchronizing the electrically excited SAW with the laser source, it is possible to measure the vertical displacement at a constant phase. The sample was moved laterally and the SAW propagation was observed.