Optical spin-orbit interaction induced by magnetic textures

TL;DR

This paper predicts that magnetic textures like skyrmions can alter the orbital angular momentum of light upon reflection, with the change governed by the light's spin angular momentum, opening new avenues in magneto-optical control.

Contribution

It introduces the novel concept that magnetic textures can modify the orbital angular momentum of light, linking spin and orbital angular momentum in magneto-optical interactions.

Findings

Orbital angular momentum of light is affected by magnetic textures.

The sign of OAM variation depends on the incident light's SAM.

Predictions are testable via circular dichroism measurements.

Abstract

Contrary to the optical spin angular momentum (SAM), the role played by the orbital angular momentum (OAM) of light in magneto-optics remains largely unexplored. However, the SAM and OAM are known to be coupled when light interacts with non-homogeneous and non-isotropic materials. Here we predict that the OAM carried by each photon in a light beam is modified upon reflection on magnetic textures like skyrmions, and that the sign of this variation is governed by the SAM of the incident field. Our predictions can be readily tested by performing circular dichroism measurements, and may provide new routes to shape light's angular momentum with magnetism.