Anomalous Hall Effect in ZrTe5

TL;DR

This study investigates the anomalous Hall effect in ZrTe$_5$, revealing its dependence on Berry curvature and Weyl nodes, with experimental evidence showing the effect's temperature and angular behavior.

Contribution

The paper provides the first detailed angular dependence measurements of the AHE in ZrTe$_5$, linking it to Berry curvature and Weyl physics without magnetic ordering.

Findings

AHE observed in all samples without magnetic order.

AHE magnitude peaks when magnetic field is in-plane.

AHE vanishes above approximately 60 K, correlating with LMR disappearance.

Abstract

ZrTe$_5$ has been of recent interest as a potential Dirac/Weyl semimetal material. Here, we report the results of experiments performed via in-situ 3D double-axis rotation to extract the full $4\pi$ solid angular dependence of the transport properties. A clear anomalous Hall effect (AHE) was detected for every sample, with no magnetic ordering observed in the system to the experimental sensitivity of torque magnetometry. Interestingly, the AHE takes large values when the magnetic field is rotated in-plane, with the values vanishing above $\sim 60$ K where the negative longitudinal magnetoresistance (LMR) also disappears. This suggests a close relation in their origins, which we attribute to Berry curvature generated by the Weyl nodes.