Topology from disorder

Steven R. White

Dan-Wei Zhang, Ling-Zhi Tang

Topological states of matter in disordered systems without translation symmetry have attracted great interest in recent years. These states with topological characters are not only robust against certain disorders, but also can be counterintuitively induced by disorders from a topologically trivial phase in the clean limit. In this review, we summarize the current theoretical and experimental progress on disorder-induced topological phases in both condensed-matter and artificial systems. We first introduce the topological Anderson insulators (TAIs) induced by random disorders and their topological characterizations and experimental realizations. We then discuss various extensions of TAIs with unique localization phenomena in quasiperiodic and non-Hermitian systems. We also review the theoretical and experimental studies on the disorder-induced topology in dynamical and many-body systems, including topological Anderson-Thouless pumps, disordered correlated topological insulators and average-symmetry protected topological orders acting as interacting TAI phases. Finally, we conclude the review by highlighting potential directions for future explorations.

Xiang Liu, Xiao-Xia Yi, Zheng‐Rong Liu +2 more

While the effects of off-diagonal disorder have been extensively studied in low-dimensional topological systems, such research remains insufficient in four-dimensional (4D) topological systems. In this work, we investigate the effect of off-diagonal disorders on a 4D topological insulator. We find that off-diagonal disorder can induce a 4D topological Anderson insulator (TAI) phase. This differs from previous finding in two-dimensional topological insulators, where off-diagonal disorder fails to induce the TAI phase. Specifically, we consider 16 different configurations of disorder and identify two distinct types based on their effect on the system. Furthermore, using the self-consistent Born approximation, we elucidate the unique role of off-diagonal disorder in these phase transitions compared to the diagonal Anderson disorder.

M. Socolovsky

Roderich Moessner, Joel E. Moore

Yiting Deng, Yan He

We study the two-dimensional disordered topological superconductor with Hubbard interactions. When the magnitude of the pairing potential is tuned to special values, this interacting model is exactly solvable even when disorders are imposed on the potential term or coupling constants. The topology of this model is investigated in detail by the real space Chern number formula, which computes the topological index of disordered systems to high precisions. It is found that the disorders can drive the system from topological trivial phase to a non-trivial phase, which generalizes the topological Anderson phenomena to interacting models. The self-consistent Born approximation is also employed to understand the influence of the disorders on the parameters of the interacting topological superconductor. It provide an alternative way to understand the topological transitions at weak disordered region.