Spin elastodynamic motive force

TL;DR

This paper theoretically investigates the spin-motive force induced by surface acoustic waves in ferromagnetic monolayers, revealing mechanisms that generate detectable electric voltages without complex device requirements.

Contribution

It introduces a new theoretical framework for spin-motive force caused by surface acoustic waves via spin-vorticity coupling, applicable to simple ferromagnetic monolayers.

Findings

Detection of electric voltages in polycrystalline nickel due to surface acoustic waves.

Identification of two mechanisms: SVC-driven and magentoelastic coupling.

Potential for broadening SMF applications without complex device structures.

Abstract

The spin-motive force (SMF) in a simple ferromagnetic monolayer caused by a surface acoustic wave is studied theoretically via spin-vorticity coupling (SVC). The SMF has two mechanisms. The first is the SVC-driven SMF, which produces the first harmonic electromotive force, and the second is the interplay between the SVC and the magentoelastic coupling, which produces the d.c. and second harmonic electromotive forces. We show that these electric voltages induced by a Rayleigh-type surface acoustic wave can be detected in polycrystalline nickel. No sophisticated device structures, non-collinear magnetic structures, or strong spin-orbit materials are used in our approach. Consequently, it is intended to broaden the spectrum of SMF applications considerably.