arXiv:1606.08911 · Oxford University Press eBooks

Quench dynamics in integrable systems

Natan Andrei, Deepak Iyer, Huijie Guan

Published Jun 23, 2016• 10 citations

Abstract

This chapter discusses aspects of the physics revealed by quantum quenches and presents a formalism for studying the quench dynamics of integrable systems. This formalism is applied to the Lieb–Liniger model of a gas of N interacting bosons moving on the continuous infinite line while interacting via a short-range potential. The quench is carried out from several initial states and for any number of particles, and the evolution of the density and the noise correlations is computed. In the long-time limit, the system dilutes and, for any value of repulsive coupling, independently of the initial state, it asymptotes toward a strongly repulsive gas, while for any value of attractive coupling, it forms a maximal bound state that dominates at longer times. In either case, the system equilibrates but does not thermalize, an effect that is consistent with prethermalization. These results can be confronted with experiments.

DOI: 10.1093/acprof:oso/9780198768166.003.0005

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