Collective dynamics of domain walls: an antiferromagnetic spin texture in an optical cavity

TL;DR

This paper explores how Dzyaloshinskii-Moriya interactions influence domain wall dynamics in an antiferromagnetic optomagnonic system, revealing new ways to measure DMI constants via cavity photon interactions.

Contribution

It demonstrates that DMI enables and modulates spin-photon coupling in optomagnonic systems, providing a novel method to measure DMI parameters.

Findings

DMI enables spin interactions with cavity photons in previously forbidden geometries.

DMI modulates resonance frequencies depending on polarization, facilitating DMI measurement.

The study offers a new approach to quantify DMI in antiferromagnetic materials using optical cavities.

Abstract

Spin canting and complex spin textures in antiferromagnetic materials can often be described in terms of Dzyaloshinskii-Moriya interactions (DMI). Values for DMI parameters are not easily measurable directly, and often inferred from other quantities. In this work, we examine how domain wall dynamics in an antiferromagnetic optomagnonic system can display unique features directly related to the existence of DMI. Our results indicate that the presence of DMI enables spin interactions with cavity photons in a geometry which otherwise allows no magneto-optical coupling, and on the other hand modulates frequencies in a geometry where coupling is already realized in the absence of DMI. This result may be used to measure the DMI constant in optomagnonic experiments by comparing resonances obtained with different polarisations of the exciting field.