Li Xuanyi, Xu Xifan, Zhou Hui, Jia Huaxian, Wang En, Fu Huixia, Sun Jia-Tao, Meng Sheng
Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
Center of Quantum Materials and Devices, College of Physics, Chongqing University, Chongqing 401331, China.
Nano Lett. 2023 Apr 12;23(7):2839-2845. doi: 10.1021/acs.nanolett.3c00154. Epub 2023 Mar 28.
The emergence of intrinsic quantum anomalous Hall (QAH) insulators with a long-range ferromagnetic (FM) order triggers unprecedented prosperity for combining topology and magnetism in low dimensions. Built upon atom-thin Chern insulator monolayer MnBr, we propose that the topologically nontrivial electronic states can be systematically tuned by inherent magnetic orders and external electric/optical fields in stacked Chern insulator bilayers. The FM bilayer illustrates a high-Chern-number QAH state characterized by both quantized Hall plateaus and specific magneto-optical Kerr angles. In antiferromagnetic bilayers, Berry curvature singularity induced by electrostatic fields or lasers emerges, which further leads to a novel implementation of the layer Hall effect depending on the chirality of irradiated circularly polarized light. These results demonstrate that abundant tunable topological properties can be achieved in stacked Chern insulator bilayers, thereby suggesting a universal routine to modulate d-orbital-dominated topological Dirac fermions.
具有长程铁磁（FM）序的本征量子反常霍尔（QAH）绝缘体的出现，引发了低维拓扑与磁性相结合的前所未有的繁荣。基于原子级薄的陈绝缘体单层MnBr，我们提出，在堆叠的陈绝缘体双层中，拓扑非平凡电子态可以通过固有磁序和外部电场/光场进行系统调控。FM双层展现出一种高陈数QAH态，其特征在于量子化的霍尔平台和特定的磁光克尔角。在反铁磁双层中，由静电场或激光诱导的贝里曲率奇点出现，这进一步导致了一种依赖于照射圆偏振光手性的新型层霍尔效应的实现。这些结果表明，在堆叠的陈绝缘体双层中可以实现丰富的可调拓扑性质，从而为调制d轨道主导的拓扑狄拉克费米子提供了一种通用方法。
