论文标题
具有嵌套带反向表面的高阶拓扑绝缘子的直接动力表征
Direct dynamical characterization of higher-order topological insulators with nested band inversion surfaces
论文作者
论文摘要
高阶拓扑绝缘子（HOTIS）是具有拓扑受保护的内部边界状态的系统，其本地化为$（d-n）$ - 维度边界，$ d $ the System dimension和$ n $ the Topology的顺序。这项工作提出了一个相当普遍的基于动态的特征，对一类$ z $ type hotis的表征，而没有特别依赖任何对称性考虑。我们创新方法的关键要素是将量子淬灭动力学与所谓的频带反转表面（BISS）的嵌套配置联系起来，动量空间汉密尔顿人作为Clifford代数的运算符的总和（可以放松的条件），从而可以动态地检测每种相等层面上的拓扑阶层。鉴于关于合成拓扑物质的实验可以直接测量某些伪蛋白纹理的绕组以确定BISS的拓扑特征，因此通过嵌套BISS定义的拓扑不变性均在正在进行的实验的范围内。此外，在定义高阶拓扑中嵌套BISS的必要性为调查和设计高阶拓扑相变提供了独特的观点。
Higher-order topological insulators (HOTIs) are systems with topologically protected in-gap boundary states localized at their $(d-n)$-dimensional boundaries, with $d$ the system dimension and $n$ the order of the topology. This work proposes a rather universal dynamics-based characterization of one large class of $Z$-type HOTIs without specifically relying on any symmetry considerations. The key element of our innovative approach is to connect quantum quench dynamics with nested configurations of the so-called band inversion surfaces (BISs) of momentum-space Hamiltonians as a sum of operators from the Clifford algebra (a condition that can be relaxed), thereby making it possible to dynamically detect each and every order of topology on an equal footing. Given that experiments on synthetic topological matter can directly measure the winding of certain pseudospin texture to determine topological features of BISs, the topological invariants defined through nested BISs are all within reach of ongoing experiments. Further, the necessity of having nested BISs in defining higher-order topology offers a unique perspective to investigate and engineer higher-order topological phase transitions.
