Quench dynamics and non equilibrium phase diagram of the Bose-Hubbard model

TL;DR

This paper studies the non-equilibrium dynamics of the Bose-Hubbard model after a quench, revealing two distinct regimes with different correlation behaviors and highlighting the role of quasi-particle interactions.

Contribution

It uncovers the existence of two non-equilibrium regimes in the Bose-Hubbard model and links these to quasi-particle interactions, providing new insights into its dynamical phase diagram.

Findings

Large interaction quenches lead to non-equilibrium steady states with memory of initial conditions.

Intermediate interaction quenches produce correlations similar to thermal equilibrium.

Two distinct non-equilibrium regimes are identified despite the model's non-integrability.

Abstract

We investigate the time evolution of correlations in the Bose-Hubbard model following a quench from the superfluid to the Mott insulating phase. For large values of the final interaction strength the system approaches a distinctly non-equilibrium steady state that bears strong memory of the initial conditions. In contrast, when the final interaction strength is comparable to the hopping, the correlations are rather well approximated by those at thermal equilibrium. The existence of two distinct non-equilibrium regimes is surprising given the non-integrability of the Bose-Hubbard model. We relate this phenomena to the role of quasi-particle interactions in the Mott insulating state.