180-degree phase shift of magnetoelastic waves observed by phase-resolved spin-wave tomography

TL;DR

This study uses phase-resolved spin-wave tomography to observe a 180-degree phase shift in magnetoelastic waves, revealing their coupling with spin and elastic waves and proposing a method for phase control via magnetization orientation.

Contribution

It demonstrates the first observation of a phase shift in magnetoelastic waves using PSWaT and introduces a technique for phase manipulation by adjusting magnetization orientation.

Findings

Detected a 180-degree phase shift at wave crossing points.

Confirmed coupling between spin and elastic waves.

Proposed a method for phase control by magnetization rotation.

Abstract

We have investigated optically-excited magnetoelastic waves by phase-resolved spin-wave tomography (PSWaT). PSWaT reconstructs dispersion relation of spin waves together with their phase information by using time-resolved magneto-optical imaging for spin-wave propagation followed by an analysis based on the convolution theorem and a complex Fourier transform. In PSWaT spectra for a Bi-doped garnet film, we found a 180 degree phase shift of magnetoelastic waves at around the crossing of the dispersion relations of spin and elastic waves. The result is explained by a coupling between spin waves and elastic waves through magnetoelastic interaction. We also propose an efficient way for phase manipulation of magnetoelastic waves by rotating the orientation of magnetization less than 10 degree.