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Critical temperature of a trapped Bose gas: comparison of theory and experiment

Matthew J. Davis·P. Blair Blakie
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Abstract

We apply the Projected Gross-Pitaevskii equation (PGPE) formalism to the experimental problem of the shift in critical temperature $T_c$ of a harmonically confined Bose gas as reported in Gerbier \emph{et al.} [Phys. Rev. Lett. \textbf{92}, 030405 (2004)]. The PGPE method includes critical fluctuations and we find the results differ from various mean-field theories, and are in best agreement with experimental data. To unequivocally observe beyond mean-field effects, however, the experimental precision must either improve by an order of magnitude, or consider more strongly interacting systems. This is the first application of a classical field method to make quantitative comparison with experiment.

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Matthew J. Davis, P. Blair Blakie. 2007-06-20. Critical temperature of a trapped Bose gas: comparison of theory and experiment. https://doi.org/10.1103/physrevlett.96.060404

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