Large intrinsic anomalous Hall effect in both Nb$_{2}$FeB$_{2}$ and Ta$_{2}$FeB$_{2}$ with collinear antiferromagnetism

TL;DR

This paper predicts large anomalous Hall effects in two collinear antiferromagnetic metals, Nb$_{2}$FeB$_{2}$ and Ta$_{2}$FeB$_{2}$, using symmetry analysis and first-principles calculations, challenging previous assumptions about AFM metals.

Contribution

It demonstrates the existence of significant AHE in collinear AFM metals and clarifies the symmetry conditions necessary for this phenomenon.

Findings

Nb$_{2}$FeB$_{2}$ has AHC of -100 Ω^{-1}cm^{-1}

Ta$_{2}$FeB$_{2}$ has AHC of -54 Ω^{-1}cm^{-1}

Both materials have Néel temperatures above room temperature

Abstract

It is rarely reported that collinear antiferromagnetic (AFM) metals can have anomalous Hall effect (AHE). In this letter, based on symmetry analysis and the first-principles electronic structure calculations, we predict that two existing collinear antiferromagnets Nb$_{2}$FeB$_{2}$ and Ta$_{2}$FeB$_{2}$, whose N\'eel temperatures are above room temperature, have very large AHE with anomalous Hall conductance (AHC) -100 $\Omega^{-1}$ cm$^{-1}$ and $-54\Omega^{-1}$ cm$^{-1}$, respectively. We further complete the symmetry resquirements for realizing the AHE in collinear antiferromagnetism.