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arXiv · 1809.07926

Experimental realization of an intrinsic magnetic topological insulator

Yan Gong·Jingwen Guo·Jiaheng Li·Kejing Zhu·Menghan Liao·Xiaozhi Liu·Qinghua Zhang·Lin Gu·Lin Tang·Xiao Feng·Ding Zhang·Wei Li·Canli Song·Lili Wang·Pu Yu·Xi Chen·Yayu Wang·Hong Yao·Wenhui Duan·Yong Xu·Shou-Cheng Zhang·Xucun Ma·Qi-Kun Xue·Ke He
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Abstract

Intrinsic magnetic topological insulator (TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel topological quantum effects but remains elusive experimentally so far. Here, we report the experimental realization of high-quality thin films of an intrinsic magnetic TI---MnBi$_2$Te$_4$---by alternate growth of a Bi$_2$Te$_3$ quintuple-layer and a MnTe bilayer with molecular beam epitaxy. The material shows the archetypical Dirac surface states in angle-resolved photoemission spectroscopy and is demonstrated to be an antiferromagnetic topological insulator with ferromagnetic surfaces by magnetic and transport measurements as well as first-principles calculations. The unique magnetic and topological electronic structures and their interplays enable the material to embody rich quantum phases such as quantum anomalous Hall insulators and axion insulators in a well-controlled way.

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Yan Gong, Jingwen Guo, Jiaheng Li, Kejing Zhu, Menghan Liao, Xiaozhi Liu, Qinghua Zhang, Lin Gu, Lin Tang, Xiao Feng, Ding Zhang, Wei Li, Canli Song, Lili Wang, Pu Yu, Xi Chen, Yayu Wang, Hong Yao, Wenhui Duan, Yong Xu, Shou-Cheng Zhang, Xucun Ma, Qi-Kun Xue, Ke He. 2018-09-21. Experimental realization of an intrinsic magnetic topological insulator. https://doi.org/10.1088/0256-307x%2F36%2F7%2F076801

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