论文标题
高阶拓扑学安德森绝缘子
Higher-order Topological Anderson Insulators
论文作者
论文摘要
我们在具有手性对称性的二维系统中研究障碍效应，发现疾病可以诱导拓扑阶段的四极拓拓基绝缘阶段（具有四极矩的高阶拓扑阶段）。它们的拓扑特性表现在基于有效的边界哈密顿量，四极力矩和零能量角模式的拓扑不变性中。我们发现宽容而无间隙的拓扑阶段和格里菲斯（Griffiths）制度。在无间隙拓扑阶段，所有状态都是局部的，而在格里菲斯（Griffiths）方面，零能量的状态变为多重分子。我们进一步应用了自以为是的天生近似，以表明诱导的拓扑阶段是由疾病重归于的肿块引起的。最终，我们引入了一种实用的实验方案，并使用托托电回路进行了实验方案，在该方案中，可以通过阻抗测量观察到预测的拓扑现象。我们的工作打开了研究高阶拓扑的安德森绝缘子及其本地化特性的大门。
We study disorder effects in a two-dimensional system with chiral symmetry and find that disorder can induce a quadrupole topological insulating phase (a higher-order topological phase with quadrupole moments) from a topologically trivial phase. Their topological properties manifest in a topological invariant defined based on effective boundary Hamiltonians, the quadrupole moment, and zero-energy corner modes. We find gapped and gapless topological phases and a Griffiths regime. In the gapless topological phase, all the states are localized, while in the Griffiths regime, the states at zero energy become multifractal. We further apply the self-consistent Born approximation to show that the induced topological phase arises from disorder renormalized masses. We finally introduce a practical experimental scheme with topoelectrical circuits where the predicted topological phenomena can be observed by impedance measurements. Our work opens the door to studying higher-order topological Anderson insulators and their localization properties.
