title: Localized phase structures growing out of quantum fluctuations in a quench of tunnel-coupled atomic condensates.
abstract: We investigate the relative phase between two weakly interacting 1D condensates of bosonic atoms after suddenly switching on the tunnel coupling. The following phase dynamics is governed by the quantum sine-Gordon equation. In the semiclassical limit of weak interactions, we observe the parametric amplification of quantum fluctuations leading to the formation of breathers with a finite lifetime. The typical lifetime and density of these "quasibreathers" are derived employing exact solutions of the classical sine-Gordon equation. Both depend on the initial relative phase between the condensates, which is considered as a tunable parameter.
authors.affiliation: Friedrich-Alexander-Universität Erlangen-Nürnberg, Institute for Theoretical Physics II, Erlangen, Germany. clemens.neuenhahn@physik.uni-erlangen.de
authors.forename: Clemens
authors.initials: C
authors.lastname: Neuenhahn
authors.forename: Anatoli
authors.initials: A
authors.lastname: Polkovnikov
authors.forename: Florian
authors.initials: F
authors.lastname: Marquardt