论文标题
无序反合对称链中的拓扑结晶相
Topological Crystalline Phases in a Disordered Inversion-Symmetric Chain
论文作者
论文摘要
当翻译对称性被散装障碍打破时,拓扑结晶系统中状态的拓扑性质可能会根据所应用的疾病的类型而变化。在这项工作中,我们表征了具有反转和手性对称性的一维(1D)链的阶段,其中每种疾病构型都是反转对称的。通过使用基本独立的公式用于反演拓扑不变,手性绕组数和散装极化,我们可以在存在无序时为这些数量构造相图。我们表明,与手性绕组数和散装极化不同,当散装频谱差距闭合强障碍时,反转拓扑不变会波动。使用位置空间重新归一化组,我们能够比较反转拓扑不变,手性绕组数和散装极化在强障碍极限下的表现低。我们表明,借助反转对称性疾病,反转拓扑不变的值取决于倒置中心的国家特征值,而诸如手性绕组数和块状极化等数量仍然来自整个链中的每个州的每个州都有贡献。我们还表明,可以通过在倒置中心占据其他状态,同时保持块状极化固定,从而改变在干净系统中反转拓扑不变的价值。我们讨论了我们的结果对高维电子系统以及超冷原子系统中拓扑结晶阶段的含义。
When translational symmetry is broken by bulk disorder, the topological nature of states in topological crystalline systems may change depending on the type of disorder that is applied. In this work, we characterize the phases of a one-dimensional (1D) chain with inversion and chiral symmetries, where every disorder configuration is inversion-symmetric. By using a basis-independent formulation for the inversion topological invariant, chiral winding number, and bulk polarization, we are able to construct phase diagrams for these quantities when disorder is present. We show that unlike the chiral winding number and bulk polarization, the inversion topological invariant can fluctuate when the bulk spectral gap closes at strong disorder. Using the position-space renormalization group, we are able to compare how the inversion topological invariant, chiral winding number and bulk polarization behave at low energies in the strong disorder limit. We show that with inversion symmetry-preserving disorder, the value of the inversion topological invariant is determined by the inversion eigenvalues of the states at the inversion centers, while quantities such as the chiral winding number and the bulk polarization still have contributions from every state throughout the chain. We also show that it is possible to alter the value of the inversion topological invariant in a clean system by occupying additional states at the inversion centers while keeping the bulk polarization fixed. We discuss the implications of our results for topological crystalline phases in higher-dimensional electronic systems, and in ultra-cold atomic systems.