# Bath-induced decay of Stark many-body localization

## TL;DR

This paper studies how a Stark-localized quantum system relaxes when coupled to a dephasing bath, revealing distinct decay behaviors compared to disorder-induced localization, with implications for ultracold atom experiments.

## Contribution

It provides a comparative analysis of Stark versus disorder-induced many-body localization decay dynamics under dephasing, highlighting unique decay and entropy growth characteristics.

## Key findings

- Imbalance decays quadratically with tilt at large potential gradients
- Exponential decay in non-interacting systems, stretched exponential with interactions
- No logarithmic entropy growth as seen in disordered systems

## Abstract

We investigate the relaxation dynamics of an interacting Stark-localized system coupled to a dephasing bath, and compare its behavior to the conventional disorder-induced many body localized system. Specifically, we study the dynamics of population imbalance between even and odd sites, and the growth of the von Neumann entropy. For a large potential gradient, the imbalance is found to decay on a time scale that grows quadratically with the Wannier-Stark tilt. For the non-interacting system, it shows an exponential decay, which becomes a stretched exponential decay in the presence of finite interactions. This is different from a system with disorder-induced localization, where the imbalance exhibits a stretched exponential decay also for vanishing interactions. As another clear qualitative difference, we do not find a logarithmically slow growth of the von-Neumann entropy as it is found for the disordered system. Our findings can immediately be tested experimentally with ultracold atoms in optical lattices.