Engineering altermagnetic symmetry to enable anomalous Hall response in Cr$_{1-x}$Mn$_x$Sb

TL;DR

This study demonstrates how partial Mn substitution in CrSb thin films can engineer symmetry to enable an anomalous Hall effect, promising for spintronic applications with high-temperature magnetic ordering.

Contribution

It introduces a method to engineer symmetry in CrSb via Mn doping to realize an anomalous Hall effect, previously symmetry-forbidden in this material class.

Findings

Pronounced anomalous Hall effect observed in Cr$_{0.75}$Mn$_{0.25}$Sb.

Landau theory models the magnetic reorientation and Hall response.

Symmetry engineering enables anomalous Hall effect in altermagnets.

Abstract

Altermagnets are a promising class of materials for spintronic applications. However, compounds that simultaneously combine the symmetry required to support an anomalous Hall effect with good metallic conductivity and magnetic ordering temperatures well above room temperature remain elusive. Here, we demonstrate that partial substitution of Cr by Mn in epitaxial CrSb(100) thin films provides a viable route to engineer the combined structural and magnetic symmetry necessary to enable an otherwise symmetry-forbidden anomalous Hall effect. By systematically exploring the magnetic phase diagram Cr$_{1-x}$Mn$_{x}$Sb thin films, we identify a pronounced anomalous Hall effect in Cr$_{0.75}$Mn$_{0.25}$Sb. Guided by Landau theory, we model the field-driven reorientation of the N\'eel vector and the resulting anomalous Hall response, achieving good qualitative agreement with the experimental observations.