Ab initio prediction of anomalous Hall effect in antiferromagnetic CaCrO$_3$

TL;DR

This study predicts a sizable anomalous Hall effect in the collinear antiferromagnetic perovskite CaCrO$_3$ using symmetry analysis and first-principles calculations, revealing Berry curvature hotspots linked to spin-orbit coupling.

Contribution

It demonstrates the presence of anomalous Hall conductivity in a collinear antiferromagnet through symmetry considerations and density-functional theory.

Findings

C-type antiferromagnetic order induces large anomalous Hall conductivity.

Berry curvature hotspots are located along gapped nodal lines.

Spin-orbit coupling enhances the anomalous Hall effect in CaCrO$_3$.

Abstract

While the anomalous Hall effect takes place typically in ferromagnets with finite magnetization, large anomalous Hall conductivity in noncollinear antiferromagnetic systems has been recently observed and attracted much attention. In this study, we predict the anomalous Hall effect in perovskite CaCrO$_3$ as a representative of 'collinear' antiferromagnetic materials. Our result shows that the C-type antiferromagnetic ordering generates the sizable anomalous Hall conductivity. Based on symmetry analyses, we show that the antiferromagnetic order parameter belongs to the same irreducible representation as the ferromagnetic order parameter in the nonsymmorphic space group, allowing the non-vanishing Berry curvatures in k space. By performing first-principles density-functional theory calculations, we find that the Berry-curvature 'hot spots' lie along the gapped nodal lines where spin-orbit coupling induces the spin splitting of Cr-3d bands near the Fermi energy and enhances the anomalous Hall effect in CaCrO$_3$.