Uniaxial strain tuned magnetism of the altermagnet candidate h-FeS

TL;DR

This study demonstrates that uniaxial strain can effectively suppress the spontaneous anomalous Hall effect and tiny net magnetization in the altermagnet candidate h-FeS, providing a means to control its magnetic and transport properties for spintronics.

Contribution

It reveals how uniaxial strain influences the magnetic and transport properties of h-FeS, an altermagnet candidate, by tuning its small ferromagnetic moment and anomalous Hall effect.

Findings

Uniaxial strain suppresses the spontaneous AHE in h-FeS.

Strain modifies the in-plane domain population without changing magnetic structure.

The tiny net magnetization correlates strongly with the AHE in h-FeS.

Abstract

Altermagnets are collinear magnetic materials with 'alter'nating local crystalline environments, characterized by joint spin and crystalline symmetries that enable ferromagnetic-like transport properties but with vanishing net magnetization. Hexagonal FeS (h-FeS) is a recently identified altermagnet candidate that shows a spontaneous anomalous Hall effect (AHE) accompanied by a tiny net magnetization. Here, we show that both the spontaneous AHE and magnetization can be effectively suppressed by an in-plane compressive strain. Since neutron diffraction measurements show that the applied uniaxial strain only modifies the in-plane domain population but does not affect the in-plane magnetic structure, the major effect of the applied strain is to tune the small $c$-axis ferromagnetic moment. Our results demonstrate a strong correlation between the tiny net magnetization and the spontaneous AHE in h-FeS, and show that uniaxial strain provides an effective knob to tune both properties in this altermagnet candidate for spintronic applications.