Inverse Faraday effect in Mott insulators

TL;DR

This paper investigates how circularly polarized light induces magnetization in Mott insulators, revealing symmetry-dependent behaviors and demonstrating tunable magnetic interactions in relevant models.

Contribution

It introduces a Floquet theory-based analysis of the inverse Faraday effect in Mott insulators, highlighting symmetry effects and potential for light-controlled magnetic interactions.

Findings

Inversion symmetry determines ferromagnetic or antiferromagnetic coupling induced by IFE.

Magnetic interactions in Hubbard models can be tuned by light.

Theoretical framework applicable to Kitaev quantum spin liquids.

Abstract

The inverse Faraday effect (IFE), where a static magnetization is induced by circularly polarized light, offers a promising route to ultrafast control of spin states. Here we study the IFE in Mott insulators using the Floquet theory. We find two distinct IFE behavior governed by the inversion symmetry. In the Mott insulators with inversion symmetry, we find that the effective magnetic field induced by the IFE couples ferromagnetically to the neighboring spins. While for the Mott insulators without inversion symmetry, the effective magnetic field due to IFE couples antiferromagnetically to the neighboring spins. We apply the theory to the spin-orbit coupled single- and multi-orbital Hubbard model that is relevant for the Kitaev quantum spin liquid material and demonstrate that the magnetic interactions can be tuned by light.