Presentation Information
[23a-A201-4]Evaluation of magnetoelastic coupling by acoustic spin Hall effect in heavy-metal/ferromagnet/rare-earth tri-layer
〇Isamu Yasuda1, Takuya Kawada2, Hiroki Matsumoto3, Masashi Kawaguchi1, Masamitsu Hayashi1 (1.The Univ. of Tokyo, 2.Osaka Univ., 3.Kyoto Univ.)
Keywords:
magnetoelastic coupling,rare-earth metal,surface acoustic wave
Surface acoustic wave (SAW) is a vibrational mode localized in vicinity of a solid surface. Previous studies have shown that SAW can excite ferromagnetic resonance via magnetoelastic coupling, and realization of strong phonon-magnon coupling in a SAW device is a milestone for quantum application such as quantum information processing and quantum sensing. For efficient phonon-magnon coupling, it is essential to enhance the magnetoelastic coupling by engineering ferromagnetic materials. In this work, we study the magnetoelastic effect in ferromagnet (FM)/Tb heterostructure, which is expected to enhance the magnetoelastic coupling because Tb-based alloy is known to exhibit giant magnetostriction constant. We evaluate the magnetoelastic coupling by a novel way to use the acoustic spin Hall effect in heavy-metal (HM)/FM/Tb tri-layer. An acoustic voltage which originates from the acoustic spin Hall effect scales with the magnitude of magnetoelastic coupling and spin orbit interaction. We find that the acoustic voltage is significantly dependent on the Tb layer thickness, implying that Tb layer plays an important role in the enhanced magnetoelastic coupling.