Collective Dynamics of Domain Walls: An Antiferromagnetic Spin Texture in an Optical Cavity

Spin canting and complex spin textures in antiferromagnetic materials can 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 polarizations of the exciting field. © 2021 American Physical Society.This work was supported by The Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery, John R. Leaders Fund–Canada Foundation for Innovation (CFI-JELF), Research Manitoba and the University of Manitoba, Canada