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arXiv · 2005.13943

Spectral signatures of the surface anomalous Hall effect in magnetic axion insulators

Mingqiang Gu·Jiayu Li·Hongyi Sun·Yufei Zhao·Chang Liu·Jianpeng Liu·Haizhou Lu·Qihang Liu
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Abstract

The topological surface states of magnetic topological systems, such as Weyl semimetals and axion insulators, are associated with unconventional transport properties such as nonzero or half-quantized surface anomalous Hall effect. Here we study the surface anomalous Hall effect and its spectral signatures in different magnetic topological phases using both model Hamiltonian and first-principles calculations. We demonstrate that by tailoring the magnetization and interlayer electron hopping, a rich three-dimensional topological phase diagram can be established, including three types of topologically distinct insulating phases bridged by Weyl semimetals, and can be directly mapped to realistic materials such as MnBi2Te4/(Bi2Te3)n systems. Among them, we find that the surface anomalous Hall conductivity in the axion-insulator phase is a well-localized quantity either saturated at or oscillating around e2/2h, depending on the magnetic homogeneity. We also discuss the resultant chiral hinge modes embedded inside the side surface bands as the potential experimental signatures for transport measurements. Our study is a significant step forward towards the direct realization of long-sought axion insulators in realistic material systems.

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Mingqiang Gu, Jiayu Li, Hongyi Sun, Yufei Zhao, Chang Liu, Jianpeng Liu, Haizhou Lu, Qihang Liu. 2021-02-10. Spectral signatures of the surface anomalous Hall effect in magnetic axion insulators. https://doi.org/10.1038/s41467-021-23844-z

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