Dynamical localization and slow dynamics in quasiperiodically-driven quantum systems

TL;DR

This paper explores how quasiperiodic driving influences localization and relaxation in disordered quantum systems, revealing phenomena like dynamical localization, destruction of Anderson localization, and drive-induced slow relaxation.

Contribution

It demonstrates that quasiperiodic drives can induce dynamical localization in clean systems, destroy Anderson localization in disordered systems, and cause logarithmic relaxation with interactions.

Findings

Quasiperiodic drive induces dynamical localization in non-interacting clean systems.

Quasiperiodic drive destroys Anderson localization in disordered systems.

Logarithmic relaxation occurs under quasiperiodic driving with interactions.

Abstract

We investigate the role of a quasiperiodically driven electric field in a one-dimensional disordered fermionic chain. In the clean non-interacting case, we show the emergence of dynamical localization - a phenomenon previously known to exist only for a perfect periodic drive. In contrast, in the presence of disorder, where a periodic drive preserves Anderson localization, we show that the quasiperiodic drive destroys it and leads to slow relaxation. Considering the role of interactions, we uncover the phenomenon of quasiperiodic driving-induced logarithmic relaxation, where a suitably tuned drive (corresponding to dynamical localization in the clean, non-interacting limit) slows down the dynamics even when the disorder is small enough for the system to be in the ergodic phase. This is in sharp contrast to the fast relaxation seen in the undriven model, as well as the absence of thermalization (drive-induced MBL) exhibited by a periodically driven model.