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arXiv · 1112.5982

Localized phase structures growing out of quantum fluctuations in a quench of tunnel-coupled atomic condensates

Clemens Neuenhahn·Anatoli Polkovnikov·Florian Marquardt
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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 the 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.

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Clemens Neuenhahn, Anatoli Polkovnikov, Florian Marquardt. 2011-12-27. Localized phase structures growing out of quantum fluctuations in a quench of tunnel-coupled atomic condensates. https://doi.org/10.1103/physrevlett.109.085304

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