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arXiv · 2401.11450

Reentrant quantum anomalous Hall effect in molecular beam epitaxy-grown MnBi2Te4 thin films

Yuanzhao Li·Yunhe Bai·Yang Feng·Jianli Luan·Zongwei Gao·Yang Chen·Yitian Tong·Ruixuan Liu·Su Kong Chong·Kang L. Wang·Xiaodong Zhou·Jian Shen·Jinsong Zhang·Yayu Wang·Chui-Zhen Chen·XinCheng Xie·Xiao Feng·Ke He·Qi-Kun Xue
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Abstract

In this study, we investigate intrinsic magnetic topological insulator MnBi2Te4 thin films grown by molecular beam epitaxy. We observe a reentrant quantum anomalous Hall effect when the Fermi energy enters the valance band and magnetic field equals zero, indicating the emergence of the Chern Anderson insulator state. The discovery opens a new avenue for realizing the QAH effect and underscores the fundamental role of both Berry curvature and Anderson localization.

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Yuanzhao Li, Yunhe Bai, Yang Feng, Jianli Luan, Zongwei Gao, Yang Chen, Yitian Tong, Ruixuan Liu, Su Kong Chong, Kang L. Wang, Xiaodong Zhou, Jian Shen, Jinsong Zhang, Yayu Wang, Chui-Zhen Chen, XinCheng Xie, Xiao Feng, Ke He, Qi-Kun Xue. 2024-01-21. Reentrant quantum anomalous Hall effect in molecular beam epitaxy-grown MnBi2Te4 thin films. https://arxiv.org/abs/2401.11450

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