Anomalous Floquet-Anderson Insulator with Quasiperiodic Temporal Noise

TL;DR

This paper investigates the stability of the anomalous Floquet-Anderson insulator under quasiperiodic temporal noise, revealing that topological phases are robust at weak noise and exhibit subdiffusive particle dynamics, with a transition to diffusive behavior at strong noise.

Contribution

It introduces a model with quasiperiodic temporal noise and demonstrates the robustness and transition of topological phases in Floquet systems under such noise conditions.

Findings

Topological phase survives weak quasiperiodic noise with stable topological pumping.

Particles exhibit subdiffusive motion within the topological phase.

Strong quasiperiodic noise destroys topology and leads to diffusive dynamics.

Abstract

Time-periodic (Floquet) drive can give rise to novel symmetry breaking and topological phases of matter. Recently, we showed that a quintessential Floquet topological phase known as the anomalous Floquet-Anderson insulator is stable to noise on the timing of its Floquet drive. Here, we perturb the anomalous Floquet-Anderson insulator at a single incommensurate frequency, resulting in a quasiperiodic 2-tone drive. Our numerics indicate that a robust topological phase survives at weak noise with topological pumping that is more stable than the case of white noise. Within the topological phase, we show that particles move subdiffusively, which is directly responsible for stabilizing topological transport. Surprisingly, we discover that when quasiperiodic noise is sufficiently strong to kill topology, the system appears to exhibit diffusive dynamics, suggesting that the correlated structure of the quasiperiodic noise becomes irrelevant.