Dynamics of a strongly interacting Fermi gas: the radial quadrupole mode

Abstract

We report on measurements of an elementary surface mode in an ultracold, strongly interacting Fermi gas of 6Li atoms. The radial quadrupole mode allows us to probe hydrodynamic behavior in the BEC-BCS crossover without being influenced by changes in the equation of state. We examine frequency and damping of this mode, along with its expansion dynamics. In the unitarity limit and on the BEC side of the resonance, the observed frequencies agree with standard hydrodynamic theory. However, on the BCS side of the crossover, a striking down shift of the oscillation frequency is observed in the hydrodynamic regime as a precursor to an abrupt transition to collisionless behavior; this indicates coupling of the oscillation to fermionic pairs.

arXiv comment11 pages, 11 figures v2: minor changes

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Cited by in corpus (36)

• Theory of ultracold Fermi gases
• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Scale invariance and viscosity of a two-dimensional Fermi gas
• Efficient all-optical production of large ${}^6$Li quantum gases using D${}_1$ gray-molasses cooling
• Collective oscillations of a Fermi gas in the unitarity limit: Temperature effects and the role of pair correlations
• Finite-Temperature Collective Dynamics of a Fermi Gas in the BEC-BCS Crossover
• Quantized Superfluid Vortex Rings in the Unitary Fermi Gas
• Collisions between tunable halo dimers: exploring an elementary four-body process with identical bosons
• Signature of the FFLO phase in the collective modes of a trapped ultracold Fermi gas
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• SU(1,1) echoes for breathers in quantum gases
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• Dipolar Fermi gases in anisotropic traps
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• Collective modes of trapped Fermi gases with in-medium interaction
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• Dynamics of shock waves in a superfluid unitary Fermi gas
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• Dipole-Mode Spectrum and Hydrodynamic Crossover in a Resonantly Interacting Two-Species Fermion Mixture
• Coupled oscillator model of a trapped Fermi gas at the BEC-BCS crossover
• Strongly Interacting Fermi Gases: Hydrodynamics and Beyond