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arXiv · 2206.14440

Intrinsic Layer-Polarized Anomalous Hall Effect in Bilayer MnBi2Te4

Rui Peng·Ting Zhang·Zhonglin He·Qian Wu·Ying Dai·Baibiao Huang·Yandong Ma
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Abstract

Layer-polarized anomalous Hall effect (LP-AHE) is an attractive phenomenon in condensed-matter physics from the standpoints of both fundamental interest and device applications. The current LP-AHE research is based on the extrinsic paradigm of using external electric fields, in which the generation and control of LP-AHE are not straightforward. Here, we propose a novel mechanism that realizes intrinsic LP-AHE in bilayer lattices, through the mediation of sliding physics and Berry curvature. Moreover, this mechanism could render the LP-AHE in a controllable and reversable fashion. We analyze the symmetry requirements for a system to host such intrinsic LP-AHE. Its validity is further demonstrated in a real material of bilayer MnBi2Te4. By stacking with broken inversion symmetry, the layer-locked Berry curvature enables the intrinsic LP-AHE in bilayer MnBi2Te4, and the switchable control of its LP-AHE is achieved by sliding ferroelectricity. Our work opens a significant new direction for LP-AHE and two-dimensional (2D) materials research.

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Rui Peng, Ting Zhang, Zhonglin He, Qian Wu, Ying Dai, Baibiao Huang, Yandong Ma. 2022-06-29. Intrinsic Layer-Polarized Anomalous Hall Effect in Bilayer MnBi2Te4. https://doi.org/10.1103/physrevb.107.085411

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