Shenzhen Institute for Quantum Science and Technology and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.
Department of Physics, South China University of Technology, Guangzhou 510640, China.
Phys Rev Lett. 2019 Aug 30;123(9):096401. doi: 10.1103/PhysRevLett.123.096401.
As a paradigmatic phenomenon in condensed matter physics, the quantum anomalous Hall effect (QAHE) in stoichiometric Chern insulators has drawn great interest for years. Using model Hamiltonian analysis and first-principles calculations, we establish a topological phase diagram and map different 2D configurations to it, which are taken from the recently grown magnetic topological insulators MnBi_{4}Te_{7} and MnBi_{6}Te_{10} with superlatticelike stacking patterns. These configurations manifest various topological phases, including the quantum spin Hall effect with and without time-reversal symmetry and QAHE. We then provide design principles to trigger the QAHE by tuning experimentally accessible knobs, such as the slab thickness and magnetization. Our work reveals that superlatticelike magnetic topological insulators with tunable exchange interactions are an ideal platform to realize the long-sought QAHE in pristine compounds, paving a new path within the area of topological materials.
作为凝聚态物理中的典范现象，化学计量 Chern 绝缘体中的量子反常霍尔效应（QAHE）多年来引起了极大的兴趣。我们使用模型哈密顿量分析和第一性原理计算，建立了拓扑相图，并将不同的 2D 构型映射到其中，这些构型取自最近生长的具有超晶格堆积模式的磁性拓扑绝缘体 MnBi_{4}Te_{7}和 MnBi_{6}Te_{10}。这些构型表现出各种拓扑相，包括具有和不具有时间反演对称性的量子自旋霍尔效应和 QAHE。然后，我们提供了通过调节实验可访问旋钮（如薄片厚度和磁化强度）来触发 QAHE 的设计原则。我们的工作表明，具有可调谐交换相互作用的超晶格磁性拓扑绝缘体是实现原始化合物中梦寐以求的 QAHE 的理想平台，为拓扑材料领域开辟了新的途径。
