Post-quench dynamics and suppression of thermalization in an open half-filled Hubbard layer

TL;DR

This paper investigates the non-equilibrium dynamics of a half-filled Hubbard layer coupled to a magnon bath after a quench, revealing regimes where thermalization is suppressed and long-lived non-equilibrium states can persist.

Contribution

It introduces a mean-field analysis of open Hubbard layers post-quench, highlighting the competition between intrinsic relaxation and bath-induced dissipation in non-thermalizing dynamics.

Findings

Long-lived non-equilibrium states can emerge despite bath coupling.

Equilibration with the bath is not guaranteed within the mean-field approximation.

Different dynamical regimes depend on the interplay between intrinsic damping and dissipation.

Abstract

We study the time evolution of a half-filled Hubbard layer coupled to a magnon bath after a quench of the Hubbard interaction. Qualitatively different regimes, regarding the asymptotic long-time dynamics, are identified and characterized within the mean-field approximation. In the absence of the bath, the dynamics of the closed system is similar to that of a quenched BCS condensate. Though the presence of the bath introduces an additional relaxation mechanism, our numerical results and analytical arguments show that equilibration with the bath is not necessarily attained within the approximations used. Instead, nonequilibrium states, similar to the ones observed in the closed system, can emerge at long times as a consequence of the competition between the intrinsic relaxation mechanism (Landau damping, for example), and the bath-induced dissipation.