Precision Measurements of Collective Oscillations in the BEC-BCS   Crossover
  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. 
A. Altmeyer, S. Riedl, C. Kohstall, M. Wright, R. Geursen, M.   Bartenstein, C. Chin, J. Hecker Denschlag, R. Grimm