Identifying Switching of Antiferromagnets by Spin-Orbit Torques

TL;DR

This paper investigates the mechanisms behind current-induced switching of antiferromagnetic order, demonstrating that ultrafast spin-orbit torques can reliably control the Neel vector in MnAu, distinguishing them from slower thermomagnetoelastic effects.

Contribution

The study experimentally distinguishes between thermomagnetoelastic effects and spin-orbit torque-driven switching in antiferromagnets, highlighting the potential for ultrafast control of magnetic order.

Findings

Thermomagnetoelastic effects dominate switching in slow regimes.

Ultrafast nanosecond pulses enable spin-orbit torque driven switching.

Complete directional control of the Neel vector achieved with current pulses.

Abstract

Antiferromagnets are promising candidates for ultrafast spintronic applications, leveraging current-induced spin-orbit torques. However, experimentally distinguishing between different switching mechanisms of the staggered magnetization (N\'eel vector) driven by current pulses remains a challenge. In an exemplary study of the collinear antiferromagnetic compound Mn$_2$Au, we demonstrate that slower thermomagnetoelastic effects predominantly govern switching over a wide parameter range. In the regime of short current pulses in the nanosecond range, however, we observe fully N\'eel spin-orbit torque driven switching. We show that this ultrafast mechanism enables the complete directional alignment of the N\'eel vector by current pulses in device structures.