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arXiv · 2206.10905

Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators

Rui Chen·Hai-Peng Sun·Mingqiang Gu·Chun-Bo Hua·Qihang Liu·Hai-Zhou Lu·X. C. Xie
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Abstract

The layer Hall effect describes electrons spontaneously deflected to opposite sides at different layers, which has been experimentally reported in the MnBi$_2$Te$_4$ thinfilms under perpendicular electric fields [Gao et al., Nature 595, 521 (2021)]. Here, we reveal a universal origin of the layer Hall effect in terms of the so-called hidden Berry curvature, as well as material design principles. Hence, it gives rise to zero Berry curvature in momentum space but nonzero layer-locked hidden Berry curvature in real space. We show that compared to that of a trivial insulator, the layer Hall effect is significantly enhanced in antiferromagnetic topological insulators. Our universal picture provides a paradigm for revealing the hidden physics as a result of the interplay between the global and local symmetries, and can be generalized in various scenarios.

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Rui Chen, Hai-Peng Sun, Mingqiang Gu, Chun-Bo Hua, Qihang Liu, Hai-Zhou Lu, X. C. Xie. 2022-06-22. Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators. https://doi.org/10.1093/nsr%2Fnwac140

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