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Equation of state and collective frequencies of a trapped Fermi gas along the BEC-unitarity crossover

G. E. Astrakharchik·R. Combescot·X. Leyronas·S. Stringari
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Abstract

We show that the study of the collective oscillations in a harmonic trap provides a very sensitive test of the equation of state of a Fermi gas near a Feshbach resonance. Using a scaling approach, whose high accuracy is proven by comparison with exact hydrodynamic solutions, the frequencies of the lowest compressional modes are calculated at T=0 in terms of a dimensionless parameter characterizing the equation of state. The predictions for the collective frequencies, obtained from the equations of state of mean field BCS theory and of recent Monte-Carlo calculations, are discussed in detail.

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G. E. Astrakharchik, R. Combescot, X. Leyronas, S. Stringari. 2005-03-25. Equation of state and collective frequencies of a trapped Fermi gas along the BEC-unitarity crossover. https://doi.org/10.1103/physrevlett.95.030404

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