论文类型：期刊论文
第一作者：Zuowei Liang
通讯作者：X-H Chen,Zhenyu Wang
合写作者：Gang Xu,Zhijun Wang,Tao Wu,J-F He,JJ Ying,Simin Nie,Qiang Zhang,Mengzhu Shi,Aiyun Luo
发表刊物：Physical Review B
收录刊物：SCI
学科门类：理学
一级学科：物理学
文献类型：J
卷号：102
期号：16
页面范围：161115
ISSN号：2469-9950
发表时间：2020-10-19
影响因子：4.036
摘要：Nontrivial band topology combined with magnetic order can lead to rich emergent phenomena, including quantized anomalous Hall effect and axion insulator state. Here we use scanning tunneling microscopy to image the surface Dirac fermions of the newly discovered magnetic topological insulators Mn Bi 2 Te 4 and Mn Bi 4 Te 7. We have determined the energy dispersion and helical spin texture of the surface states through quasiparticle interference patterns far above Dirac energy. Approaching the Dirac point, the native defects in the Mn Bi 2 Te 4 septuple layer give rise to resonance states which extend spatially and potentially hinder the detection of a mass gap in the spectra. Our results impose tight constraints on the magnitude of the possible mass gap at the nanoscale and provide key ingredients for a comprehensive understanding of the electronic structure in this class of fascinating materials.