论文标题
Wannier乐队的过渡$π$ -Flux梯子
Wannier band transitions in disordered $π$-flux ladders
论文作者
论文摘要
边界阻塞的拓扑绝缘子是一类不寻常的高阶拓扑绝缘子，其拓扑特性由所谓的Wannier带确定。边界阻塞的相位可以藏有铰链/角模式，但是这些模式通常会因边界上的相变而不是散装而不稳定。尽管在存在障碍中拓扑绝缘子的稳定性方面有很多工作，但尚未广泛研究了无序的沉迷带和无序引起的Wannier转变的拓扑。在这项工作中，我们专注于Wannier拓扑绝缘子的最简单示例：一维镜子对称$π$ -Flux梯子。我们发现，Wannier拓扑对于无序是可靠的，并得出了真正的空间重新归一化组程序，可以理解一种新型的强障碍诱导的非平凡和琐碎的Wannier拓扑阶段之间的过渡。我们还建立了梯子拓扑的拓扑结构与具有物理边界削减的相关系统的能量谱带拓扑之间的联系，这通常是针对干净模型的猜想，但尚未在存在障碍的情况下进行研究。
Boundary obstructed topological insulators are an unusual class of higher-order topological insulators with topological characteristics determined by the so-called Wannier bands. Boundary obstructed phases can harbor hinge/corner modes, but these modes can often be destabilized by a phase transition on the boundary instead of the bulk. While there has been much work on the stability of topological insulators in the presence disorder, the topology of a disordered Wannier band, and disorder-induced Wannier transitions have not been extensively studied. In this work, we focus on the simplest example of a Wannier topological insulator: a mirror-symmetric $π$-flux ladder in 1D. We find that the Wannier topology is robust to disorder, and derive a real-space renormalization group procedure to understand a new type of strong disorder-induced transition between non-trivial and trivial Wannier topological phases. We also establish a connection between the Wannier topology of the ladder and the energy band topology of a related system with a physical boundary cut, something which has generally been conjectured for clean models, but has not been studied in the presence of disorder.
