Experimental Observation of a Generalized Gibbs Ensemble
Abstract
The connection between the non-equilibrium dynamics of isolated quantum many-body systems and statistical mechanics is a fundamental open question. It is generally believed that the unitary quantum evolution of a sufficiently complex system leads to an apparent maximum-entropy state that can be described by thermodynamical ensembles. However, conventional ensembles fail to describe the large class of systems that exhibit non-trivial conserved quantities. Instead, generalized ensembles have been predicted to maximize entropy in these systems. In our experiments we explicitly show that a degenerate one-dimensional Bose gas relaxes to a state that can be described by such a generalized ensemble. This is verified through a detailed study of correlation functions up to 10th order. The applicability of the generalized ensemble description for isolated quantum many-body systems points to a natural emergence of classical statistical properties from the microscopic unitary quantum evolution.
Cite
@article{arxiv.1411.7185,
title = {Experimental Observation of a Generalized Gibbs Ensemble},
author = {Tim Langen and Sebastian Erne and Remi Geiger and Bernhard Rauer and Thomas Schweigler and Maximilian Kuhnert and Wolfgang Rohringer and Igor E. Mazets and Thomas Gasenzer and Jörg Schmiedmayer},
journal= {arXiv preprint arXiv:1411.7185},
year = {2015}
}
Comments
5 pages + 4 pages supp. mat., 4 figures