Large Zeeman splitting induced anomalous Hall effect in ZrTe5

Zeliang Sun,Zhipeng Cao,Xianhui Chen,Xiangang Wan,Zhaohui Cheng,Zhenyu Wang,Changsheng Zhu,Honghui Wang,Donghui Ma,Jianhua Cui,Weizhuang Zhuo

doi:10.1038/s41535-020-0239-z

Abstract

Berry phase effects have significant influences on the electronic properties of condensed matter. In particular, the anomalous Hall conductivity has been recognized as an intrinsic property of the systems with non-zero Berry curvature. Here, we present the anomalous Hall effect observed in the non-magnetic material ZrTe5, which hosts a large Zeeman splitting with Landé g-factor of 26.49. The quantum oscillation analysis reveals non-linear band dispersion near the top of valence band in bulk band structure, and no Weyl node forms with applied magnetic field. The anomalous Hall conductivity reaches 129 Ω−1 cm−1 at 2 K, and shows weak temperature dependence. All these combined with theoretical analysis suggest that the anomalous Hall effect observed in ZrTe5 originates from the non-vanishing Berry curvature induced by combining large Zeeman splitting and strong spin–orbit coupling. Remarkably, the anomalous Hall resistivity reverses its sign from negative to positive at a hydrostatic pressure P = 1.3 GPa, which confirms that the anomalous Hall effect in ZrTe5 is highly related to the band structure-dependent Berry curvature. Our results have verified the anomalous Hall mechanism in ZrTe5 and offer a new platform to study the anomalous Hall effect.

Highlights

The ordinary Hall effect arises from the Lorentz force bending of charge carriers’ path under a magnetic field
The anomalous Hall effect (AHE) occurs due to the transverse velocity of carriers, which can be engendered by two classes of mechanisms[1,2]: the extrinsic mechanism owing to spin-dependent impurity scattering effects[3,4,5], including skew-scattering and side jump, and the intrinsic mechanism, which is related to the nonzero Berry curvature[1,2,6,7,8,9]
The intrinsic mechanism is only dependent on the band structure and it is proposed that the non-zero Berry curvature can generate an anomalous velocity in the direction transverse to the electric field and external magnetic field, which gives rise to an anomalous Hall current resulting in intrinsic contribution to the Hall conductivity[10,11,12,13,14]

Summary

INTRODUCTION

The ordinary Hall effect arises from the Lorentz force bending of charge carriers’ path under a magnetic field. The intrinsic mechanism is only dependent on the band structure and it is proposed that the non-zero Berry curvature can generate an anomalous velocity in the direction transverse to the electric field and external magnetic field, which gives rise to an anomalous Hall current resulting in intrinsic contribution to the Hall conductivity[10,11,12,13,14]. Our work indicates the AHE observed in ZrTe5 arises from the Berry curvature generated from combining large Zeeman splitting and strong SOC, and provides a new insight into searching and studying the anomalous Hall effect in real materials

RESULTS AND DISCUSSION

METHODS

CODE AVAILABILITY