Twisted light-induced spin-spin interaction in a chiral helimagnet

TL;DR

This paper explores how optical vortex beams can influence chiral magnetic order in a metal, proposing a new interaction mechanism that could enable novel opto-spintronics device functionalities.

Contribution

It introduces a microscopic interaction model between optical vortex beams and electrons in a chiral helimagnet, revealing a new way to modulate magnetic order.

Findings

Optical vortex beams can modulate chiral magnetic order.

The interaction differs fundamentally from magnetic field effects.

Potential for creating topological or chiral structures for spintronics.

Abstract

We theoretically investigate how the orbital angular momentum of light can affect a chiral magnetic order. Here, we consider a metallic chiral helimagnet, which is under stationary radiation of a resonant optical vortex beam. We propose a novel interaction between local spins considering microscopic interactions between an optical vortex and electrons. This vortex-induced interaction modulates the chiral magnetic order in an entirely different way than an external magnetic field does. Our spin modulation technique may pave a route to create a unique topological or chiral structure for future opto-spintronics devices.