Open questions for strongly interacting Fermi gases with zero-range interactions

Yvan Castin

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arXiv · 2410.20866

Open questions for strongly interacting Fermi gases with zero-range interactions

Yvan Castin

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Abstract

We review some unresolved theoretical issues in three-dimensional two-component Fermi gases, drawing on recent experiments on cold atoms in immaterial traps close to a magnetic Feshbach resonance. We distinguish successively (i) the open questions arising in the few-body problem with Wigner-Bethe-Peierls contact interactions - essentially the stability of the gas with respect to the Efimov effect and the calculation of the cluster (or virial) coefficients, (ii) those arising in the effective low-energy theory of Landau and Khalatnikov quantum hydrodynamics - essentially the damping of phonon modes and the coherence time of the condensate of pairs, and finally (iii) questions requiring a complete, microscopic solution of the many-body problem, such as the specific properties of the acoustic excitation branch (Goldstone) of the condensate of pairs, or its collective excitation branch (Higgs) in the broken-pair continuum.

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Yvan Castin. 2024-10-28. Open questions for strongly interacting Fermi gases with zero-range interactions. https://arxiv.org/abs/2410.20866

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