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Quantum fluctuations in one-dimensional arrays of condensates

Alessandro Cuccoli·Andrea Fubini·Valerio Tognetti·Ruggero Vaia
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Abstract

The effects of quantum and thermal fluctuations upon the fringe structure predicted to be observable in the momentum distribution of coupled Bose-Einstein condensates are studied by the effective-potential method. For a double-well trap, the coherence factor recently introduced by Pitaevskii and Stringari [Phys. Rev. Lett. 87, 180402 (2001)] is calculated using the effective potential approach and is found in good agreement with their result. The calculations are extended to the case of a one-dimensional array of condensates, showing that quantum effects are essentially described through a simple renormalization of the energy scale in the classical analytical expression for the fringe structure. The consequences for the experimental observability are discussed.

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Alessandro Cuccoli, Andrea Fubini, Valerio Tognetti, Ruggero Vaia. 2001-11-08. Quantum fluctuations in one-dimensional arrays of condensates. https://doi.org/10.1103/physreva.64.061601

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