Linear magnetization dependence and large intrinsic anomalous Hall effect in Fe78Si9B13 metallic glasses

TL;DR

This paper investigates the anomalous Hall effect in Fe78Si9B13 metallic glasses, revealing an intrinsic, dissipationless mechanism with a linear magnetization dependence and suggesting potential topological properties in these amorphous materials.

Contribution

It is the first to demonstrate a linear magnetization dependence of anomalous Hall conductivity in metallic glasses, indicating a dominant intrinsic mechanism and proposing topological features.

Findings

Intrinsic anomalous Hall conductivity is linearly dependent on magnetization.

Normalized anomalous Hall conductivity is independent of longitudinal conductivity.

Large intrinsic anomalous Hall conductivity suggests possible topological properties.

Abstract

The origin of anomalous Hall effect (AHE) in ferromagnetic metallic glasses (MGs) is not yet understood completely. Here, the AHE is explored in Fe78Si9B13 MGs. We find the behavior of resistivity at low temperature seems to be more likely due to structure effect rather than Kondo-type effect. More importantly, we firstly find the primitive experiment anomalous Hall conductivity ({\sigma}AH) without separation of extrinsic contribution has a linear magnetization (Mz) dependence when temperature is changing, which is another feature of intrinsic mechanism and indicates intrinsic contribution is dominated. Furthermore, the {\sigma}AH normalized by Mz is independent of longitudinal conductivity ({\sigma}xx), which shows the characteristic of dissipationless intrinsic mechanism. We suggest the intrinsic contribution can be understood from the density of Berry curvature integrated over occupied energies proposed for aperiodic materials recently, and the linear magnetization dependence can be understood qualitatively from the fluctuations of spin orientation and the proportional relationship between Berry curvature and magnetization. Moreover, based on the recent theory report of topological amorphous metals, we make a prediction that the large intrinsic {\sigma}AH (616 S/cm) in Fe78Si9B13 MGs implies some topological properties of MGs waiting for further discovery.