Ultrafast coherent all-optical switching of an antiferromagnet with the inverse Faraday effect

TL;DR

This paper demonstrates that circularly polarized laser pulses can achieve ultrafast, coherent, all-optical switching of antiferromagnetic order in CrPt within a few hundred femtoseconds, using the inverse Faraday effect.

Contribution

It introduces a combined theoretical approach to show how the inverse Faraday effect enables reliable, nonthermal ultrafast switching in antiferromagnets.

Findings

Switching occurs within a few hundred femtoseconds.

Switching is driven by the inverse Faraday effect inducing staggered magnetic moments.

The process involves elliptical magnetic trajectories leading to two perpendicular states.

Abstract

We explore the possibility of ultrafast, coherent all-optical magnetization switching in antiferromagnets by studying the action of the inverse Faraday effect in CrPt, an easy-plane antiferromagnet. Using a combination of density functional theory and atomistic spin dynamics simulations, we show how a circularly polarized laser pulse can switch the order parameter of the antiferromagnet within a few hundred femtoseconds. This nonthermal switching takes place on an elliptical path, driven by the staggered magnetic moments induced by the inverse Faraday effect and leading to reliable switching between two perpendicular magnetic states.