Quantum fluctuations in one-dimensional arrays of condensates - art. no. 061601

The effects of quantum and thermal fluctuations upon the fringe structure p redicted to be observable in the momentum distribution of coupled Bose-Eins tein condensates are studied by the effective-potential method. For a doubl e-well trap, the coherence factor recently introduced by Pitaevskii and Str ingari (e-print cond-mat/0104458) is calculated using the effective potenti al approach and is found in good agreement with their result. The calculati ons are extended to the case of a one-dimensional array of condensates, sho wing that quantum effects are essentially described through a simple renorm alization of the energy scale in the classical analytical expression for th e fringe structure. The consequences for the experimental observability are discussed.