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arXiv · 0711.3627

Collective Excitations of Trapped Imbalanced Fermion Gases

Achilleas Lazarides·Bert Van Schaeybroeck
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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.

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Achilleas Lazarides, Bert Van Schaeybroeck. 2008-03-17. Collective Excitations of Trapped Imbalanced Fermion Gases. https://doi.org/10.1103/physreva.77.041602

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