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.
Palestini F., PIERI, P., STRINATI CALVANESE, G. (2012). Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime. PHYSICAL REVIEW LETTERS, 108(8), 080401-1-080401-4 [10.1103/PhysRevLett.108.080401].
Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime
PIERI, Pierbiagio;
2012
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.