论文标题
反转对称原子绝缘子之间的拓扑状态
Topological states between inversion symmetric atomic insulators
论文作者
论文摘要
拓扑绝缘子的标志之一是其块状拓扑的值与在有限大小的样本中观察到的拓扑保护边缘模式之间的对应关系。对于强大的拓扑不变性，已经对这种散装的对应关系进行了充分的测试，并构成了所有拟议的拓扑技术应用的基础。在这里，我们报告说，仅取决于原子晶格的对称性的一组弱拓扑不变性也会诱导特定类型的散装式对应关系。它预测了基于连接点两侧的频段的空间组表示，它们的强度不变剂的两个反合对称带绝缘子之间的界面中存在或不存在具有琐碎值的界面的状态。我们表明，这与拓扑材料的基于对称性的分类相对应。界面模式受界面拓扑结合和界面对称性的组合进行保护，可用于基于异质结的设备中的拓扑传输和信号操纵。
One of the hallmarks of topological insulators is the correspondence between the value of its bulk topological invariant and the number of topologically protected edge modes observed in a finite-sized sample. This bulk-boundary correspondence has been well-tested for strong topological invariants, and forms the basis for all proposed technological applications of topology. Here, we report that a group of weak topological invariants, which depend only on the symmetries of the atomic lattice, also induces a particular type of bulk-boundary correspondence. It predicts the presence or absence of states localised at the interface between two inversion-symmetric band insulators with trivial values for their strong invariants, based on the space group representation of the bands on either side of the junction. We show that this corresponds with symmetry-based classifications of topological materials. The interface modes are protected by the combination of band topology and symmetry of the interface, and may be used for topological transport and signal manipulation in heterojunction-based devices.
