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Precision Measurements of Collective Oscillations in the BEC-BCS Crossover

A. Altmeyer·S. Riedl·C. Kohstall·M. Wright·R. Geursen·M. Bartenstein·C. Chin·J. Hecker Denschlag·R. Grimm
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Abstract

We report on precision measurements of the frequency of the radial compression mode in a strongly interacting, optically trapped Fermi gas of Li-6 atoms. Our results allow for a test of theoretical predictions for the equation of state in the BEC-BCS crossover. We confirm recent quantum Monte-Carlo results and rule out simple mean-field BCS theory. Our results show the long-sought beyond-mean-field effects in the strongly interacting BEC regime.

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A. Altmeyer, S. Riedl, C. Kohstall, M. Wright, R. Geursen, M. Bartenstein, C. Chin, J. Hecker Denschlag, R. Grimm. 2006-12-17. Precision Measurements of Collective Oscillations in the BEC-BCS Crossover. https://doi.org/10.1103/physrevlett.98.040401

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