Driving magnetic skyrmions with microwave fields

TL;DR

This paper demonstrates theoretically that microwave magnetic fields can move magnetic skyrmions and skyrmion lattices by breaking their symmetry, with velocity depending on field parameters and resonance conditions.

Contribution

It introduces a novel method to manipulate skyrmions using microwave fields, revealing the dependence on resonance and symmetry-breaking effects.

Findings

Skyrmions can be moved with microwave fields when symmetry is broken.

Maximum skyrmion velocity occurs at resonance frequency of the breathing mode.

Velocity depends on microwave amplitude, frequency, and in-plane magnetic field strength.

Abstract

We show theoretically by numerically solving the Landau-Lifshitz-Gilbert equation with a classical spin model on a two-dimensional system that both magnetic skyrmions and skyrmion lattices can be moved with microwave magnetic fields. The mechanism is enabled by breaking the axial symmetry of the skyrmion, for example through application of a static in-plane external field. The net velocity of the skyrmion depends on the frequency and amplitude of the microwave fields as well as the strength of the in-plane field. The maximum velocity is found where the frequency of the microwave coincides with the resonance frequency of the breathing mode of the skyrmions.