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arXiv · 1506.03056

Traveling surface spin-wave resonance spectroscopy using surface acoustic waves

Praveen G. Gowtham·Takahiro Moriyama·Daniel C. Ralph·Robert A. Buhrman
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Abstract

Coherent gigahertz-frequency surface acoustic waves (SAWs) traveling on the surface 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 q enforced by the SAW, can be detected by measuring changes in the electro-acoustical transmission of a SAW delay line. Here, we provide a first demonstration that such measurements constitute a precise and quantitative technique for spin-wave spectroscopy, providing a means to determine both isotropic and anisotropic contributions to the spin-wave dispersion and damping. We demonstrate the effectiveness of this spectroscopic technique by measuring the spin-wave properties of a Ni thin film for a large range of wave vectors,q = 2.5 x 10^4 - 8 x 10^4 cm^(-1), over which anisotropic dipolar interactions vary from being negligible to quite significant.

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Praveen G. Gowtham, Takahiro Moriyama, Daniel C. Ralph, Robert A. Buhrman. 2016-03-09. Traveling surface spin-wave resonance spectroscopy using surface acoustic waves. https://doi.org/10.1063/1.4938390

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