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arXiv · 0902.0611

Dissipation induced coherence and stochastic resonance of an open two-mode Bose-Einstein condensate

D. Witthaut·F. Trimborn·S. Wimberger
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Abstract

We discuss the dynamics of a Bose-Einstein condensate in a double-well trap subject to phase noise and particle loss. The phase coherence of a weakly-interacting condensate, experimentally measured via the contrast in an interference experiment, as well as the response to an external driving become maximal for a finite value of the dissipation rate matching the intrinsic time scales of the system. This can be understood as a stochastic resonance of the many-particle system. Even stronger effects are observed when dissipation acts in concurrence with strong inter-particle interactions, restoring the purity of the condensate almost completely and increasing the phase coherence significantly. Our theoretical results are backed by Monte Carlo simulations, which show a good qualitative agreement and provide a microscopic explanation for the observed stochastic resonance effect.

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D. Witthaut, F. Trimborn, S. Wimberger. 2009-02-03. Dissipation induced coherence and stochastic resonance of an open two-mode Bose-Einstein condensate. https://doi.org/10.1103/physreva.79.033621

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