Liang Aiji, Chen Cheng, Zheng Huijun, Xia Wei, Huang Kui, Wei Liyang, Yang Haifeng, Chen Yujie, Zhang Xin, Xu Xuguang, Wang Meixiao, Guo Yanfeng, Yang Lexian, Liu Zhongkai, Chen Yulin
School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China.
Nano Lett. 2022 Jun 8;22(11):4307-4314. doi: 10.1021/acs.nanolett.1c04930. Epub 2022 May 23.
The topological electronic structure plays a central role in the nontrivial physical properties in topological quantum materials. A minimal, "hydrogen-atom-like" topological electronic structure is desired for research. In this work, we demonstrate an effort toward the realization of such a system in the intrinsic magnetic topological insulator MnBiTe, 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 MnBiTe 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 MnBiTe but also provides possible new routes in accentuating the topological behavior in the magnetic topological quantum materials.
拓扑电子结构在拓扑量子材料的非平凡物理性质中起着核心作用。研究需要一种最小的、“类氢原子”的拓扑电子结构。在这项工作中，我们展示了通过表面修饰来操控拓扑表面态（TSS），从而在本征磁性拓扑绝缘体MnBiTe中实现这样一个系统的努力。利用基于高分辨率激光和同步加速器的角分辨光电子能谱（ARPES），我们发现MnBiTe中的TSS与平凡的Rashba型表面态（RSS）严重杂化，而通过原位表面钾（K）掺杂可以有效地去除这种杂化。通过采用多种实验方法对K掺杂表面进行表征，我们将这种修饰归因于表面K团簇的电化学反应。我们的工作不仅在MnBiTe中给出了清晰的能带归属，而且为突出磁性拓扑量子材料中的拓扑行为提供了可能的新途径。
