TY  - JOUR
AU  - Qian, Guojian
AU  - Shi, Mengzhu
AU  - Chen, Hui
AU  - Zhu, Shiyu
AU  - Hu, Jiawei
AU  - Huang, Zihao
AU  - Huang, Yuan
AU  - Chen, Xian-Hui
AU  - Gao, Hong-Jun
PY  - 2023
TI  - Spin-flop transition and Zeeman effect of defect-localized bound states in the antiferromagnetic topological insulator MnBi2Te4
JO  - Nano Research
SN  - 1998-0124
SP  - 1101
EP  - 1106
VL  - 16
IS  - 1
AB  - The correlation of surface impurity states with the antiferromagnetic ground states is crucial for understanding the formation of the topological surface state in the antiferromagnetic topological insulators MnBi2Te4. By using low-temperature scanning tunneling microscopy and spectroscopy, we observed a localized bound state around the Mn-Bi antisite defect at the Te-terminated surface of the antiferromagnetic topological insulator MnBi2Te4. When applying a magnetic field perpendicular to the surface (Bz) from –1.5 to 3.0 T, the bound state shifts linearly to a lower energy with increasing Bz, which is attributed to the Zeeman effect. Remarkably, when applying a large range of Bz from –8.0 to 8.0 T, the magnetic field induced reorientation of surface magnetic moments results in an abrupt jump in the local density of states (LDOS), which is characterized by LDOS-change-ratio  dσ~/dB quantitatively. Interestingly, two asymmetric critical field, –2.0  and 4.0 T determined by the two peaks in  dσ~/dB are observed, which is consistent with simulated results according to a Mills-model, describing a surface spin flop transition (SSF). Our results provide a new flatform for studying the interplay between magnetic order and topological phases in magnetic topological materials.
UR  - https://doi.org/10.1007/s12274-022-4685-8
DO  - 10.1007/s12274-022-4685-8