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arXiv · 0810.1796

The Non-universal behaviour of Cold Fermi Condensates with Narrow Feshbach Resonances

Chi-Yong Lin·Da-Shin Lee·Ray J. Rivers
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Abstract

In this paper we construct an effective field theory for a condensate of cold Fermi atoms whose scattering is controlled by a narrow Feshbach resonance. We show how, from first principles, it permits a hydrodynamic description of the BEC-BCS crossover from which the equation of state, intimately related to the speed of sound, can be derived. Specifically, we stress the non-universal behaviour of the equation of state at the unitary limit of infinite scattering length that arises when either, or both, of the range of the inter-atomic force and the scale of the molecular field become large.

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Chi-Yong Lin, Da-Shin Lee, Ray J. Rivers. 2008-10-10. The Non-universal behaviour of Cold Fermi Condensates with Narrow Feshbach Resonances. https://doi.org/10.1103/physreva.80.043621

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