论文标题
对高阶拓扑的实验观察Anderson绝缘子
Experimental Observation of Higher-Order Topological Anderson Insulators
论文作者
论文摘要
最近,已经提出了一个新的受对称性保护的高阶拓扑绝缘子,并被证明具有较低维度的边界状态。但是,由于散装中存在强障碍,晶体对称性被打破,相关的角状态消失了。众所周知,可以通过将足够的疾病添加到拓扑琐碎的绝缘子中,即所谓的拓扑安德森绝缘子,从而诱发稳健边缘状态和量化运输的出现。问题是疾病是否也可能导致高阶拓扑阶段。到目前为止,这尚不清楚,因为疾病与高阶拓扑阶段之间的相互作用与一阶拓扑系统的相互作用完全不同。在这里,我们从理论上证明了这种疾病诱导的高阶拓扑角状态和量化分数角电荷可能会出现在改良的haldane模型中。在实验中,我们使用电路构建了如此高级拓扑的Anderson绝缘子的经典类似物,并通过电压测量观察了障碍诱导的角状态。我们的工作不认为该疾病对高阶拓扑阶段有害,并提供了一个可行的平台来研究疾病与高阶拓扑阶段之间的相互作用。
Recently, a new family of symmetry-protected higher-order topological insulators has been proposed and was shown to host lower-dimensional boundary states. However, with the existence of the strong disorder in the bulk, the crystal symmetry is broken, and the associated corner states are disappeared. It is well known that the emergence of robust edge states and quantized transport can be induced by adding sufficient disorders into a topologically trivial insulator, that is the so-called topological Anderson insulator. The question is whether disorders can also cause the higher-order topological phase. This is not known so far, because interactions between disorders and the higher-order topological phases are completely different from those with the first-order topological system. Here, we demonstrate theoretically that the disorderinduced higher-order topological corner state and quantized fraction corner charge can appear in a modified Haldane model. In experiments, we construct the classical analog of such higherorder topological Anderson insulators using electric circuits and observe the disorder-induced corner state through the voltage measurement. Our work defies the conventional view that the disorder is detrimental to the higher-order topological phase, and offers a feasible platform to investigate the interaction between disorders and higher-order topological phases.