Persistent oscillations versus thermalization in the quench dynamics of quantum gases with long-range interactions

TL;DR

This paper investigates how quantum gases with long-range interactions exhibit either persistent oscillations or thermalization after a quench, revealing the role of long-range interactions in nonergodic dynamics relevant to quantum information.

Contribution

It demonstrates that long-range interactions, not conserved quantities, drive nonergodic behavior in quantum quench dynamics of bosonic models, with implications for experimental quantum systems.

Findings

Long-range interactions cause nonthermalized oscillations or thermalization.

Initial states determine the long-time dynamical behavior.

Long-range nature, not conserved quantities, drives nonergodic dynamics.

Abstract

Searching for nonthermalized dynamics in interacting quantum systems is not only of fundamental theoretical interest in nonequilibrium quantum physics, but also of immense practical significance in quantum information processing. In this paper, we study quantum quench dynamics in an hard-core bosonic model with infinite-range interactions, which have been realized in recent high-finesse cavity experiments. We show the long-time dynamics of this model can exhibit either undamped oscillations or thermalization depending on the choice of initial states. The long-range nature of the interactions rather than conserved quantities are responsible for such nonergodic dynamical behaviors.