Evolution of Berry curvature and reentrant quantum anomalous Hall effect in an intrinsic magnetic topological insulator  

作　　者：Chui-Zhen Chen Junjie Qi Dong-Hui Xu XinCheng Xie 

机构地区：[1]Institute for Advanced Study and School of Physical Science and Technology,Soochow University,Suzhou 215006,China [2]Beijing Academy of Quantum Information Sciences,Beijing 100193,China [3]Department of Physics,Hubei University,Wuhan 430062,China [4]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [5]CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2021年第12期138-143,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDB28000000);the National Basic Research Program of China (Grant No.2019YFA0308403);the National Natural Science Foundation of China (Grant Nos.11534001,12074108,11704106,and 11974256);funded by the Natural Science Foundation of Jiangsu Province (Grant No.BK20190813);the Priority Academic Program Development of Jiangsu Higher Education Institutions;supported by the Chutian Scholars Program in Hubei Province。

摘　　要：Recently, the magnetic topological insulator(TI) MnBi2Te4 emerged as a competitive platform to realize quantum anomalous Hall(QAH) states. We report a Berry curvature splitting mechanism to realize the QAH effect in the disordered magnetic TI multilayers when switching from an antiferromagnetic order to a ferromagnetic order. We reveal that the splitting of spin-resolved Berry curvature, originating from the separation of the critical points during the magnetic switching, can give rise to a QAH insulator. We present a global phase diagram, and also provide a phenomenological picture to elucidate the Berry curvature splitting mechanism by the evolution of topological charges. At last, we predict that the Berry curvature splitting mechanism will lead to a reentrant QAH effect, which can be detected by tuning the gate voltage. Our theory will be instructive for the studies of the QAH effect in MnBi2Te4 in future experiments.

关 键 词：quantum anomalous Hall effect Berry curvature DISORDER localization 

分 类 号：O469[理学—凝聚态物理]