Large anomalous Hall effect driven by non-vanishing Berry curvature in non-collinear antiferromagnetic Mn3Ge

Understand

It is well established that the anomalous Hall effect that a ferromagnet displays scales with its magnetization.

• Therefore, an antiferromagnet that has no net magnetization should exhibit no anomalous Hall effect.
• Here we show that the non-collinear triangular antiferromagnet Mn3Ge exhibits a large anomalous Hall effect comparable to that of ferromagnetic metals; the magnitude of the anomalous conductivity is 500 per ohm per cm at 2 K and 50 per ohm per cm at room temperature.
• The angular dependence of the anomalous Hall effect measurements confirm that the small residual in-plane magnetic moment has no role in the observed effect.