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arXiv:1104.0890 · Physical Review Letters

Effects of Interactions on the Critical Temperature of a Trapped Bose Gas

Robert P. Smith, Robert L. D. Campbell, Naaman Tammuz, Zoran Hadzibabic

Published Jun 23, 2011• 93 citations
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Abstract

We perform high-precision measurements of the condensation temperature of a harmonically trapped atomic Bose gas with widely tunable interactions. For weak interactions we observe a negative shift of the critical temperature in excellent agreement with mean-field theory. However for sufficiently strong interactions we clearly observe an additional positive shift, characteristic of beyond-mean-field critical correlations. We also discuss nonequilibrium effects on the apparent critical temperature for both very weak and very strong interactions.

DOI
10.1103/physrevlett.106.250403

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