Traveling surface spin-wave resonance spectroscopy using surface acoustic waves

摘要

Coherent gigahertz-frequency surface acoustic waves (SAWs) traveling on thesurface of a piezoelectric crystal can, via the magnetoelastic interaction,resonantly excite traveling spin waves in an adjacent thin-film ferromagnet.These excited spin waves, traveling with a definite in-plane wave-vector qenforced by the SAW, can be detected by measuring changes in theelectro-acoustical transmission of a SAW delay line. Here, we provide a firstdemonstration that such measurements constitute a precise and quantitativetechnique for spin-wave spectroscopy, providing a means to determine bothisotropic and anisotropic contributions to the spin-wave dispersion anddamping. We demonstrate the effectiveness of this spectroscopic technique bymeasuring the spin-wave properties of a Ni thin film for a large range of wavevectors,q = 2.5 x 10^4 - 8 x 10^4 cm^(-1), over which anisotropic dipolarinteractions vary from being negligible to quite significant.