Band splitting induced Berry flux and intrinsic anomalous Hall conductivity in NiCoMnGa quaternary Heusler compound

TL;DR

This study investigates the anomalous Hall effect in NiCoMnGa Heusler compounds, combining experimental measurements and theoretical calculations to reveal the role of Berry flux and spin-orbit coupling in intrinsic conductivity.

Contribution

It provides the first combined experimental and theoretical analysis of AHE in NiCoMnGa, highlighting the intrinsic Berry flux contribution due to spin-orbit coupled band splitting.

Findings

Experimental AHC of 256 S/cm at 10K

Intrinsic AHC contribution of ~121 S/cm

Theoretical intrinsic AHC of about 100 S/cm

Abstract

The anomalous transport properties of Heusler compounds become a hotspot of research in recent years due to their unique band structure and possible application in spintronics. In this paper, we report the anomalous Hall effect in polycrystalline NiCoMnGa quaternary Heusler compound by experimental means and theoretical calculations. The experimental anomalous Hall conductivity (AHC) was found at about 256 S/cm at 10K with an intrinsic contribution of ~ 121 S/cm. The analysis of Hall data reveals the presence of both extrinsic and intrinsic contributions in AHE. Our theoretical calculations show that a pair of spin-orbit coupled band formed by the band splitting due to spin-orbit interaction (SOI) at the Fermi level produces a finite Berry flux in the system that provides the intrinsic AHC about 100 S/cm, which is in good agreement with the experiment.