Interactions of spin waves with a magnetic vortex

TL;DR

This study explores how azimuthal spin waves interact with magnetic vortices in ferromagnetic disks, revealing size-dependent mode splitting caused by coupling with vortex core dynamics.

Contribution

It provides new insights into the coupling mechanism between spin waves and vortex core motion in nanoscale magnetic structures.

Findings

Mode splitting increases as disk size decreases

Coupling between spin waves and vortex core causes mode doublet formation

Size-dependent behavior of azimuthal spin-wave modes

Abstract

We have investigated azimuthal spin-wave modes in magnetic vortex structures using time-resolved Kerr microscopy. Spatially resolved phase and amplitude spectra of ferromagnetic disks with diameters from 5 $\mu$m down to 500 nm reveal that the lowest order azimuthal spin wave mode splits into a doublet as the disk size decreases. We demonstrate that the splitting is due to the coupling between spin waves and the gyrotropic motion of the vortex core.