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 (6)Li 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 Bose-Einstein condensation (BEC) regime.
Altmeyer
A
A
Institute of Experimental Physics, Center for Quantum Physics, University of Innsbruck, 6020 Innsbruck, Austria.
Riedl
S
S
Kohstall
C
C
Wright
M J
MJ
Geursen
R
R
Bartenstein
M
M
Chin
C
C
Denschlag
J Hecker
JH
Grimm
R
R