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Four-body problem and BEC-BCS crossover in a quasi-one-dimensional cold fermion gas

C. Mora·A. Komnik·R. Egger·A. O. Gogolin
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Abstract

The four-body problem for an interacting two-species Fermi gas is solved analytically in a confined quasi-one-dimensional geometry, where the two-body atom-atom scattering length $a_{aa}$ displays a confinement-induced resonance. We compute the dimer-dimer scattering length $a_{dd}$, and show that this quantity completely determines the many-body solution of the associated BEC-BCS crossover phenomenon in terms of bosonic dimers.

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C. Mora, A. Komnik, R. Egger, A. O. Gogolin. 2005-08-22. Four-body problem and BEC-BCS crossover in a quasi-one-dimensional cold fermion gas. https://doi.org/10.1103/physrevlett.95.080403

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