Giant Piezospintronic Effect in a Noncollinear Antiferromagnetic Metal

TL;DR

This paper demonstrates a giant piezoelectric strain effect on the spin structure and anomalous Hall resistance in a noncollinear antiferromagnetic metal, enabling high signal output for spintronic devices at room temperature.

Contribution

It introduces a method to control antiferromagnetic spin structures via piezoelectric strain and constructs tunnel junctions with enhanced resistance ratios, advancing antiferromagnetic spintronics.

Findings

Giant piezoelectric strain control of spin structure in Mn3Ga.

Room-temperature tunnel junctions with >10% resistance ratio.

Potential for high-density, large-signal antiferromagnetic devices.

Abstract

One of the main bottleneck issues for room-temperature antiferromagnetic spintronic devices is the small signal read-out owing to the limited anisotropic magnetoresistance in antiferromagnets. However, this could be overcome by either utilizing the Berry-curvature-induced anomalous Hall resistance in noncollinear antiferromagnets or establishing tunnel junction devices based on effective manipulation of antiferromagnetic spins. In this work, we demonstrate the giant piezoelectric strain control of the spin structure and the anomalous Hall resistance in a noncollinear antiferromagnetic metal - D019 hexagonal Mn3Ga. Furthermore, we built tunnel junction devices with a diameter of 200 nm to amplify the maximum tunneling resistance ratio to more than 10% at room-temperature, which thus implies significant potential of noncollinear antiferromagnets for large signal-output and high-density antiferromagnetic spintronic device applications.