Robustness of quantum many-body scars in the presence of Markovian bath

TL;DR

This paper investigates how quantum many-body scars (QMBS) in weakly ergodic systems are affected by Markovian dissipation, revealing that such systems can relax to steady states dominated by QMBS and exhibit revivals, with implications for experimental realization.

Contribution

It extends the understanding of quantum many-body scars to open systems with Markovian baths, showing the persistence of QMBS and coherent dynamics under dissipation.

Findings

System relaxes to a QMBS-dominated steady state.

Dissipative dynamics show revivals with proper initial states.

Experimental setup with cold atoms can realize controlled dissipation.

Abstract

A generic closed quantum many-body system will inevitably tend to thermalization, whose local information encoded in the initial state eventually scrambles into the full space, known as quantum ergodicity. A paradigmatic exception in closed quantum systems for strong ergodicity breaking is known as many-body localization, where strong disorder-induced localization prevents the occurrence of thermalization. It is generally recognized that a localized quantum system would be delocalized under dissipation induced by the environment. However, this consequence recently has received challenges where an exotic dissipation-induced localization mechanism is proposed, and transitions between localized and extended phases are found. In this Letter, we promote this mechanism to systems for weak ergodicity breaking hosting quantum many-body scars (QMBS). We find that the system relaxes to a steady state dominated by QMBS, and the dissipative dynamics exhibit dynamic revivals by suitably preparing an initial state. We point out an experimental realization of the controlled dissipation with a cold atomic setup. This makes the signature of ergodicity breaking visible over dissipative dynamics and offers potential possibilities for experimentally preparing stable QMBS with associated coherent dynamics.