论文标题
使用自旋厅电导率作为拓扑签名发现高阶拓扑绝缘子
Discovery of Higher-Order Topological Insulators using the Spin Hall Conductivity as a Topology Signature
论文作者
论文摘要
拓扑绝缘子的发现和实现，这是一个物质的阶段，当$ d $ d $ d $ dimensimention sistrulating Bunk限制在（$ d-1 $） - 尺寸时，导致了几种潜在的应用程序。最近，已经表明，受保护的拓扑状态可以在（$ d-2 $）中表现出 - 分别用于三维系统和二维系统的铰链和角状态。这些非平凡的材料被命名为高阶拓扑绝缘子（HOTIS）。在这里，我们使用{\ it i ab intib}计算和紧密结合建模的组合显示了自旋大厅效应和热门之间的联系。该模型展示了非零的中Midgap自旋电导率（SHC）如何在HOTI阶段出现。之后，我们使用SHC作为标准进行了高通量密度功能理论计算以找到未知的HOTIS。我们计算了693个绝缘子的SHC，导致七个稳定的二维HOTIS。我们的工作指导了针对高阶拓扑绝缘子实现和应用的新型实验和理论进步。
The discovery and realization of topological insulators, a phase of matter which hosts metallic boundary states when the $d$-dimension insulating bulk is confined to ($d-1$)-dimensions, led to several potential applications. Recently, it was shown that protected topological states can manifest in ($d-2$)-dimensions, such as hinge and corner states for three- and two-dimensional systems, respectively. These nontrivial materials are named higher-order topological insulators (HOTIs). Here we show a connection between spin Hall effect and HOTIs using a combination of {\it ab initio} calculations and tight-binding modeling. The model demonstrates how a non-zero bulk midgap spin Hall conductivity (SHC) emerges within the HOTI phase. Following this, we performed high-throughput density functional theory calculations to find unknown HOTIs, using the SHC as a criterion. We calculated the SHC of 693 insulators resulting in seven stable two-dimensional HOTIs. Our work guides novel experimental and theoretical advances towards higher-order topological insulators realization and applications.
