Approaching a Minimal Topological Electronic Structure in Antiferromagnetic Topological Insulator MnBi2Te4 via Surface Modification

Aiji Liang; Cheng Chen; Huijun Zheng; Wei Xia; Kui Huang; Liyang Wei; Haifeng Yang; Yujie Chen; Xin Zhang; Xuguang Xu; Meixiao Wang; Yanfeng Guo; Lexian Yang; Zhongkai Liu; Yulin Chen

doi:10.1021/acs.nanolett.1c04930

arXiv · 2205.10804

Approaching a Minimal Topological Electronic Structure in Antiferromagnetic Topological Insulator MnBi2Te4 via Surface Modification

Aiji Liang·Cheng Chen·Huijun Zheng·Wei Xia·Kui Huang·Liyang Wei·Haifeng Yang·Yujie Chen·Xin Zhang·Xuguang Xu·Meixiao Wang·Yanfeng Guo·Lexian Yang·Zhongkai Liu·Yulin Chen

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Abstract

The topological electronic structure plays a central role in the non-trivial physical properties in topological quantum materials. A minimal, hydrogen-atom-like topological electronic structure is desired for researches. In this work, we demonstrate an effort towards the realization of such a system in the intrinsic magnetic topological insulator MnBi2Te4, by manipulating the topological surface state (TSS) via surface modification. Using high resolution laser- and synchrotron-based angle-resolved photoemission spectroscopy (ARPES), we found the TSS in MnBi2Te4 is heavily hybridized with a trivial Rashba-type surface state (RSS), which could be efficiently removed by the in situ surface potassium (K) dosing. By employing multiple experimental methods to characterize K dosed surface, we attribute such a modification to the electrochemical reactions of K clusters on the surface. Our work not only gives a clear band assignment in MnBi2Te4, but also provides possible new routes in accentuating the topological behavior in the magnetic topological quantum materials.

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Aiji Liang, Cheng Chen, Huijun Zheng, Wei Xia, Kui Huang, Liyang Wei, Haifeng Yang, Yujie Chen, Xin Zhang, Xuguang Xu, Meixiao Wang, Yanfeng Guo, Lexian Yang, Zhongkai Liu, Yulin Chen. 2022-05-22. Approaching a Minimal Topological Electronic Structure in Antiferromagnetic Topological Insulator MnBi2Te4 via Surface Modification. https://doi.org/10.1021/acs.nanolett.1c04930

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