Light-Induced Control of Magnetic Phases in Kitaev Quantum Magnets

TL;DR

This paper demonstrates how circularly-polarized light can dynamically control magnetic phases in the Kitaev magnet $ ext{RuCl}_3$, enabling the exploration of quantum spin liquids and magnetic instabilities through light-induced effects.

Contribution

It introduces a novel light-driven magneto-electric effect in Kitaev magnets, showing how tailored light pulses can manipulate magnetic interactions and induce quantum spin liquid states.

Findings

Light induces a large dynamical magnetic field in $ ext{RuCl}_3$

Tailored light pulses can steer the system towards a Kitaev quantum spin liquid

Transient magnetic exchange processes can be observed via pump-probe spectroscopy

Abstract

Leveraging coherent light-matter interaction in solids is a promising new direction towards control and functionalization of quantum materials, to potentially realize regimes inaccessible in equilibrium and stabilize new or useful states of matter. We show how driving the strongly spin-orbit coupled proximal Kitaev magnet $\alpha$-RuCl$_3$ with circularly-polarized light can give rise to a novel ligand-mediated magneto-electric effect that both photo-induces a large dynamical effective magnetic field and dramatically alters the interplay of competing isotropic and anisotropic exchange interactions. We propose that tailored light pulses can nudge the material towards the elusive Kitaev quantum spin liquid as well as probe competing magnetic instabilities far from equilibrium, and predict that the transient competition of magnetic exchange processes can be readily observed via pump-probe spectroscopy.