论文标题
无序的四极杆绝缘子的拓扑相变
Topological Phase Transitions in Disordered Electric Quadrupole Insulators
论文作者
论文摘要
我们研究了量化的电二极杆绝缘子中疾病驱动的拓扑相变。我们表明，手性对称性可以保护四极力矩$ q_ {xy} $的量化，从而使高阶拓扑不变性也是明确的，即使疾病破坏了所有结晶对称性。此外，可以通过保留手性对称性的无序疾病从微不足道的绝缘阶段诱导$ q_ {xy} $，随之而来的角模式。这种拓扑相变的临界点即使在存在强障碍的情况下，也会出现扩展的边界状态。我们提供了来自大量和边界描述的这些无序驱动的拓扑相变的系统表征。
We investigate disorder-driven topological phase transitions in quantized electric quadrupole insulators. We show that chiral symmetry can protect the quantization of the quadrupole moment $q_{xy}$, such that the higher-order topological invariant is well-defined even when disorder has broken all crystalline symmetries. Moreover, nonvanishing $q_{xy}$ and consequent corner modes can be induced from a trivial insulating phase by disorder that preserves chiral symmetry. The critical points of such topological phase transitions are marked by the occurrence of extended boundary states even in the presence of strong disorder. We provide a systematic characterization of these disorder-driven topological phase transitions from both bulk and boundary descriptions.
