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arXiv 2201.00988cond-mat.mes-hallcond-mat.dis-nncond-mat.quant-gasquant-ph
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准周期链中具有不同体态的拓扑Anderson绝缘体

Topological Anderson insulators with different bulk states in quasiperiodic chains

Ling-Zhi Tang, Shu-Na Liu, Guo-Qing Zhang, Dan-Wei Zhang

摘要:

本文研究了具有准周期跳跃调制的一维厄米和非厄米Su-Schrieffer-Heeger链的拓扑和局部化。在厄米情况下,通过数值和解析计算各种拓扑和局域化特征得到相图。我们表明存在的拓扑扩展,中间,和本地化的阶段,由于独立的拓扑和本地化相变的准周期性的障碍驱动的共存。与一维随机无序系统中的无隙和局域化TAI相不同,我们发现了三种类型的准无序诱导的带隙拓扑安德森绝缘体(TAI),在这个手性链中具有扩展,中间(具有迁移率边缘)和局域体态。此外,我们还分别从非共轭复跳变相位和非对称跳变强度两个方面研究了非厄米效应对TAI的影响。我们证明了三种类型的TAI在非Hermitian扰动下保持一些独特的局部化和拓扑性质,如非Hermitian实复形和局部化跃迁及其拓扑性质。我们的工作表明,在厄米特和非厄米特准周期系统的无序诱导TAI不依赖于安德森跃迁,并有各种本地化属性。

英文摘要:

We investigate the topology and localization of one-dimensional Hermitian and non-Hermitian Su-Schrieffer-Heeger chains with quasiperiodic hopping modulations. In the Hermitian case, phase diagrams are obtained by numerically and analytically calculating various topological and localization characters. We show the presence of topological extended, intermediate, and localized phases due to the coexistence of independent topological and localization phase transitions driven by the quasiperiodic disorder. Unlike the gapless and localized TAI phase in one-dimensional random disordered systems, we uncover three types of quasiperiodic-disorder-induced gapped topological Anderson insulators (TAIs) with extended, intermediate (with mobility edges), and localized bulk states in this chiral chain. Moreover, we study the non-Hermitian effects on the TAIs by considering two kinds of non-Hermiticities from the non-conjugate complex hopping phase and asymmetric hopping strength, respectively. We demonstrate that three types of TAIs preserve under the non-Hermitian perturbations with some unique localization and topological properties, such as the non-Hermitian real-complex and localization transitions and their topological nature. Our work demonstrates that the disorder-induced TAIs in Hermitian and non-Hermitian quasiperiodic systems are not tied to Anderson transitions and have various localization properties.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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