Anomalous Hall effect from gapped nodal line in Co2FeGe Heusler compound

TL;DR

This study investigates the anomalous Hall effect in Co2FeGe Heusler compound, revealing that gapped nodal lines near the Fermi level cause significant intrinsic Hall conductivity, confirmed by experiments and first-principles calculations.

Contribution

It demonstrates that gapped nodal lines are the main source of AHE in Co2FeGe, combining experimental measurements with theoretical calculations.

Findings

AHC of 100 S/cm at room temperature

Intrinsic contribution of 78 S/cm to AHC

Berry curvature from gapped nodal line drives AHE

Abstract

Full Heusler compounds with Cobalt as a primary element show anomalous transport properties owing to the Weyl fermions and broken time-reversal symmetry. We present here the study of anomalous Hall effect (AHE) in Co2FeGe Heusler compound. The experiment reveals anomalous Hall conductivity (AHC) 100 S/cm at room temperature with an intrinsic contribution of 78 S/cm . The analysis of anomalous Hall resistivity suggests the scattering independent intrinsic mechanism dominates the overall behaviour of anomalous Hall resistivity. The first principles calculation reveals that the Berry curvature originated by gapped nodal line near EF is the main source of AHE in Co2FeGe Heusler compound. The theoretically calculated AHC is in agreement with the experiment.