Strong orientation dependent spin-orbit torque in antiferromagnet Mn2Au

TL;DR

This paper investigates the orientation-dependent spin-orbit torque switching in Mn2Au antiferromagnetic films, revealing distinct switching behaviors based on crystal orientation and demonstrating potential for versatile spintronic applications.

Contribution

It provides the first detailed study of orientation-dependent SOT switching in Mn2Au films, highlighting how crystal orientation influences switching characteristics and anisotropy effects.

Findings

Orientation-dependent reversible switching observed in Mn2Au films.

Negligible anisotropy leads to direction-independent switching.

Magnetocrystalline anisotropy affects switching efficiency along hard axes.

Abstract

Antiferromagnets with zero net magnetic moment, strong anti-interference and ultrafast switching speed have potential competitiveness in high-density information storage. Body centered tetragonal antiferromagnet Mn2Au with opposite spin sub-lattices is a unique metallic material for N\'eel-order spin-orbit torque (SOT) switching. Here we investigate the SOT switching in quasi-epitaxial (103), (101) and (204) Mn2Au films prepared by a simple magnetron sputtering method. We demonstrate current induced antiferromagnetic moment switching in all the prepared Mn2Au films by a short current pulse at room temperature, whereas different orientated films exhibit distinguished switching characters. A direction-independent reversible switching is attained in Mn2Au (103) films due to negligible magnetocrystalline anisotropy energy, while for Mn2Au (101) and (204) films, the switching is invertible with the current applied along the in-plane easy axis and its vertical axis, but becomes attenuated seriously during initially switching circles when the current is applied along hard axis, because of the existence of magnetocrystalline anisotropy energy. Besides the fundamental significance, the strong orientation dependent SOT switching, which was not realized irrespective of ferromagnet and antiferromagnet, provides versatility for spintronics.