Physics (Internal)

Generalized Gibbs ensemble (GGE) and applications for integrable systems

This event is part of the Condensed Matter Theory Seminar Series.

Abstract: We study the nonequilibrium properties of 1-D interacting systems. For the 1-D Lieb Liniger gas we introduce a new version of the Yudson representation applicable to finite size systems. We provide a formalism to compute various correlation functions for highly nonequilibrium initial states. In the strong coupling regime we are able to find explicit expressions for the density, density-density and related correlation functions. We are able to show that for initial sates with smooth correlations the gas equilibrates at long times. For nearly translationaly invariant states the gas equilibrates to the GGE. We show that for other integrable models, ones with bound states, the GGE fails. We also apply our results on equilibration and the GGE to studying initial states with small Yang-Yang entropies in the Tonks Girardeau regime. We show that at long time such states have universal power law density-density correlations.