Mapping Dirac fermions in the intrinsic antiferromagnetic topological insulators (MnBi2Te4)(Bi2Te3)n ( n=0,1 )
- Resource Type
- Authors
- Zuowei Liang; Zhenyu Wang; Aiyun Luo; M. Z. Shi; Tao Wu; Zhijun Wang; Qiang Zhang; Gang Xu; Simin Nie; Junfeng He; X. H. Chen; J. J. Ying
- Source
- Physical Review B. 102
- Subject
- Physics
Condensed matter physics
02 engineering and technology
Electronic structure
021001 nanoscience & nanotechnology
01 natural sciences
symbols.namesake
Dirac fermion
Hall effect
Topological insulator
0103 physical sciences
Quasiparticle
symbols
Antiferromagnetism
010306 general physics
0210 nano-technology
Mass gap
Surface states
- Language
- ISSN
- 2469-9969
2469-9950
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 $\mathrm{Mn}{\mathrm{Bi}}_{2}{\mathrm{Te}}_{4}$ and $\mathrm{Mn}{\mathrm{Bi}}_{4}{\mathrm{Te}}_{7}$. 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 $\mathrm{Mn}{\mathrm{Bi}}_{2}{\mathrm{Te}}_{4}$ 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.