论文标题
量子旋转厅绝缘子中的真实空间阻塞
Real-space Obstruction in Quantum Spin Hall Insulators
论文作者
论文摘要
迄今为止，已将最近引入的二维绝缘子分类用于拓扑结晶不变剂，以“阻塞”原子绝缘子，其特征在于电子Wannier函数和离子位置之间的不匹配。我们将此概念扩展到量子自旋霍尔绝缘子，其中无法用时间反转对称的局部渗透函数来描述基态。通过对称分析以及密度函数理论来鉴定并研究了与石墨烯所有相关的电子和拓扑特性相当于其所有相关电子和拓扑特性的系统。低能模型包括局部自旋轨道耦合和非本地对称性破坏电势，事实证明这是阻塞量子自旋霍尔绝缘子的必需成分。然后，在大间隙三角量子旋转大厅材料中测量梗阻的实验指纹。
The recently introduced classification of two-dimensional insulators in terms of topological crystalline invariants has been applied so far to "obstructed" atomic insulators characterized by a mismatch between the centers of the electronic Wannier functions and the ionic positions. We extend this notion to quantum spin Hall insulators in which the ground state cannot be described in terms of time-reversal symmetric localized Wannier functions. A system equivalent to graphene in all its relevant electronic and topological properties except for a real-space obstruction is identified and studied via symmetry analysis as well as with density functional theory. The low-energy model comprises a local spin-orbit coupling and a non-local symmetry breaking potential, which turn out to be the essential ingredients for an obstructed quantum spin Hall insulator. An experimental fingerprint of the obstruction is then measured in a large-gap triangular quantum spin Hall material.
