ARPES investigation of the electronic structure and its evolution in magnetic topological insulator MnBi2+2 nTe4+3 n family

Runzhe Xu; Lixuan Xu; Zhongkai Liu; Lexian Yang; Yulin Chen

doi:10.1093/nsr/nwad313

ARPES investigation of the electronic structure and its evolution in magnetic topological insulator MnBi_{2+2 n}Te_{4+3 n} family

Natl Sci Rev. 2024 Jan 8;11(2):nwad313. doi: 10.1093/nsr/nwad313. eCollection 2024 Feb.

Authors

Runzhe Xu¹, Lixuan Xu^{1

2}, Zhongkai Liu^{2

3}, Lexian Yang^{1

4

5}, Yulin Chen^{2

3

6}

Affiliations

¹ State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
² School of Physical Science and Technology, ShanghaiTech University and CAS-Shanghai Science Research Center, Shanghai 201210, China.
³ ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China.
⁴ Frontier Science Center for Quantum Information, Beijing 100084, China.
⁵ Collaborative Innovation Center of Quantum Matter, Beijing 100871, China.
⁶ Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, UK.

Abstract

In the past 5 years, there has been significant research interest in the intrinsic magnetic topological insulator family compounds MnBi₂₊₂_nTe₄₊₃_n (where n = 0, 1, 2 …). In particular, exfoliated thin films of MnBi₂Te₄ have led to numerous experimental breakthroughs, such as the quantum anomalous Hall effect, axion insulator phase and high-Chern number quantum Hall effect without Landau levels. However, despite extensive efforts, the energy gap of the topological surface states due to exchange magnetic coupling, which is a key feature of the characteristic band structure of the system, remains experimentally elusive. The electronic structure measured by using angle-resolved photoemission (ARPES) shows significant deviation from ab initio prediction and scanning tunneling spectroscopy measurements, making it challenging to understand the transport results based on the electronic structure. This paper reviews the measurements of the band structure of MnBi₂₊₂_nTe₄₊₃_n magnetic topological insulators using ARPES, focusing on the evolution of their electronic structures with temperature, surface and bulk doping and film thickness. The aim of the review is to construct a unified picture of the electronic structure of MnBi₂₊₂_nTe₄₊₃_n compounds and explore possible control of their topological properties.

Keywords: MnBi2Te4; angle-resolved photoemission spectroscopy; electronic structure; magnetic topological insulator.

Publication types

Review