arXiv:2103.14388 · Physical Review A

Effective thermalization of a many-body dynamically localized Bose gas

Vincent Vuatelet, Adam Rançon

Published Oct 4, 2021• 17 citations

Abstract

Dynamical localization is the analog of Anderson localization in momentum space, where the system's energy saturates and the single-particle wave functions are exponentially localized in momentum space. In the presence of interactions, in the context of a periodically kicked Bose gas, it has been argued that dynamical localization persists. Focusing on the Tonks (strongly interacting) regime, we show that the many-body dynamically localized phase is effectively thermal, a clear deviation from the breaking of ergodicity observed in standard many-body localized systems. We relate the effective temperature to the driving parameters, and thus quantitatively describe the loss of coherence at large distances in this phase. Contrary to the noninteracting case, the momentum distribution decays as a power-law at large momenta, characterized by an effectively thermal Tan's contact. This is a rare example where driving and many-body (dynamical) localization lead to an effectively ergodic state.

DOI: 10.1103/physreva.104.043302

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