Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime

F. Palestini; P. Pieri; G. C. Strinati

doi:10.1103/physrevlett.108.080401

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arXiv · 1201.4035

Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime

F. Palestini·P. Pieri·G. C. Strinati

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Abstract

Recent experimental advances in ultra-cold Fermi gases allow for exploring response functions under different dynamical conditions. In particular, the issue of obtaining a "quasi-repulsive" regime starting from a Fermi gas with an attractive inter-particle interaction while avoiding the formation of the two-body bound state is currently debated. Here, we provide a calculation of the density and spin response for a wide range of temperature and coupling both in the attractive and quasi-repulsive regime, whereby the system is assumed to evolve non-adiabatically toward the "upper branch" of the Fermi gas. A comparison is made with the available experimental data for these two quantities.

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F. Palestini, P. Pieri, G. C. Strinati. 2012-01-19. Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime. https://doi.org/10.1103/physrevlett.108.080401

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