Collective Excitations of Trapped Imbalanced Fermion Gases

Abstract

We present a theoretical study of the collective excitations of a trapped imbalanced fermion gas at unitarity, when the system consists of a superfluid core and a normal outer shell. We formulate the relevant boundary conditions and treat the normal shell both hydrodynamically and collisionlessly. For an isotropic trap, we calculate the mode frequencies as a function of trap polarization. Out-of-phase modes with frequencies below the trapping frequency are obtained for the case of a hydrodynamic normal shell. For the collisionless case, we calculate the monopole mode frequencies, and find that all but the lowest mode may be damped.

4 pages; accepted for publication in PRA

References in corpus (5)

• Direct Observation of the Superfluid Phase Transition in Ultracold Fermi Gases
• Deformation of a Trapped Fermi Gas with Unequal Spin Populations
• Pairing without Superfluidity: The Ground State of an Imbalanced Fermi Mixture
• Surface Tension in Unitary Fermi Gases with Population Imbalance
• Normal-Superfluid Interface Scattering For Polarized Fermion Gases

Cited by in corpus (6)

• Ultra-cold Polarized Fermi Gases
• Interface Tension of Bose-Einstein Condensates
• Trapped Phase-Segregated Bose-Fermi Mixtures and their Collective Excitations
• Normal-Superfluid Interface for Polarized Fermion Gases
• BEC immersed in a Fermi sea: Theory of static and dynamic behavior across phase separation
• Collective Excitations of Harmonically Trapped Ideal Gases