Interaction quenches in the 1D Bose gas

The non-equilibrium dynamics of integrable systems are special: there is substantial evidence that after a quantum quench they do not thermalize but their asymptotic steady state can be described by a Generalized Gibbs Ensemble (GGE). Most of the studies on the GGE so far have focused on models that can be mapped to quadratic systems while analytic treatment in non-quadratic systems remained elusive. We obtain results on interaction quenches in a non-quadratic continuum system, the 1D Bose gas described by the integrable Lieb-Liniger model. We compute local correlators for a non-interacting initial state and arbitrary final interactions as well as two-point functions for quenches to the Tonks-Girardeau regime. We show that in the long time limit integrability leads to significant deviations from the predictions of the grand canonical ensemble.Comment: Supersedes arXiv:1204.3889. 4+ pages + Supplementary Materia

Real-time confinement following a quantum quench to a non-integrable model

Quarks cannot be observed as free particles in nature because they are confined into baryons and mesons, as a result of the fact that the strong interaction between them increases with their separation. However, it is less known that this phenomenon also occurs in condensed matter and statistical physics as experimentally proved in several quasi-1D compounds. Most of the theoretical and experimental studies so far concentrated on understanding the consequences of confinement for the equilibrium physics of both high-energy and condensed matter systems. Here, instead we show that confinement has dramatic consequences for the non-equilibrium dynamics following a quantum quench and that these e ects could be exploited as a quantitative probe of confinement