Current induced switching in Mn2Au from first principles

TL;DR

This study combines first-principles calculations and spin dynamics simulations to understand current-induced switching in Mn2Au antiferromagnet, highlighting the roles of spin-orbit torques and thermal activation.

Contribution

It introduces a multiscale model integrating ab initio and atomistic simulations to analyze switching mechanisms in Mn2Au, emphasizing the importance of thermal effects.

Findings

Induced magnetic moments are too small for deterministic switching.

Thermal activation is necessary to overcome energy barriers.

Switching paths and timescales are characterized.

Abstract

It is well established that it is possible to switch certain antiferromagnets electrically, yet the interplay of N\'{e}el-spin-orbit torques and thermal activation is only poorly understood. Combining ab initio calculations and atomistic spin dynamics simulations we develop a multiscale model to study the current induced switching in Mn2Au. We compute from first principles the strength and direction of the electrically induced magnetic moments, caused by the Rashba--Edelstein effect, and take these into account in atomistic spin dynamics simulations. Our simulations reveal the switching paths as well as the time scales for switching. The size of the induced moments, however, turns out to be insufficient to lead to fully deterministic switching. Instead, we find that a certain degree of thermal activation is required to help overcoming the relevant energy barrier.