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Phase-fluctuating 3D condensates in elongated traps

D. S. Petrov·G. V. Shlyapnikov·J. T. M. Walraven
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Abstract

We find that in very elongated 3D trapped Bose gases, even at temperatures far below the BEC transition temperature Tc, the equilibrium state will be a 3D condensate with fluctuating phase (quasicondensate). At sufficiently low temperatures the phase fluctuations are suppressed and the quasicondensate turns into a true condensate. The presence of the phase fluctuations allows for extending thermometry of Bose-condensed gases well below those established in current experiments.

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D. S. Petrov, G. V. Shlyapnikov, J. T. M. Walraven. 2001-04-26. Phase-fluctuating 3D condensates in elongated traps. https://doi.org/10.1103/physrevlett.87.050404

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