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Collective modes of trapped gases at the BEC-BCS crossover

H. Heiselberg
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Abstract

The collective mode frequencies in isotropic and deformed traps are calculated for general polytropic equation of states, $P\propto n^{γ+1}$, and expressed in terms of $γ$ and the trap geometry. For molecular and standard Bose-Einstein condensates and Fermi gases near Feshbach resonances, the effective power $γ\simeq0.5-1.3$ is calculated from Jastrow type wave-function ansätze, and from the crossover model of Leggett. The resulting mode frequencies are calculated for these phases around the BCS-BEC crossover.

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H. Heiselberg. 2004-06-14. Collective modes of trapped gases at the BEC-BCS crossover. https://doi.org/10.1103/physrevlett.93.040402

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