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Feshbach resonance in dense ultracold Fermi gases

R. Combescot
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Abstract

We propose a coherent framework allowing to deal with many-body effects in dense ultracold Fermi gases in the presence of a Feshbach resonance. We show that the simple effect of Pauli exclusion induces a strong modification of the basic scattering properties, leading in particular to an energy dependence of the effective scattering length on the scale of the chemical potential. This results in a smearing of the Feshbach resonance and provides a natural explanation for recent experimental findings.

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R. Combescot. 2003-02-11. Feshbach resonance in dense ultracold Fermi gases. https://doi.org/10.1103/physrevlett.91.120401

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