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arXiv · 0707.3593

Finite-Temperature Collective Dynamics of a Fermi Gas in the BEC-BCS Crossover

M. J. Wright·S. Riedl·A. Altmeyer·C. Kohstall·E. R. Sanchez Guajardo·J. Hecker Denschlag·R. Grimm
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Abstract

We report on experimental studies on the collective behavior of a strongly interacting Fermi gas with tunable interactions and variable temperature. A scissors mode excitation in an elliptical trap is used to characterize the dynamics of the quantum gas in terms of hydrodynamic or near-collisionless behavior. We obtain a crossover phase diagram for collisional properties, showing a large region where a non-superfluid strongly interacting gas shows hydrodynamic behavior. In a narrow interaction regime on the BCS side of the crossover, we find a novel temperature-dependent damping peak, suggesting a relation to the superfluid phase transition.

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M. J. Wright, S. Riedl, A. Altmeyer, C. Kohstall, E. R. Sanchez Guajardo, J. Hecker Denschlag, R. Grimm. 2007-07-24. Finite-Temperature Collective Dynamics of a Fermi Gas in the BEC-BCS Crossover. https://doi.org/10.1103/physrevlett.99.150403

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