title: Equation of state of a Fermi gas in the BEC-BCS crossover: a quantum Monte Carlo study.
abstract: We calculate the equation of state of a two-component Fermi gas with attractive short-range interspecies interactions using the fixed-node diffusion Monte Carlo method. The interaction strength is varied over a wide range by tuning the value a of the s-wave scattering length of the two-body potential. For a>0 and a smaller than the inverse Fermi wave vector our results show a molecular regime with repulsive interactions well described by the dimer-dimer scattering length a(m)=0.6a. The pair correlation functions of parallel and opposite spins are also discussed as a function of the interaction strength.
authors.affiliation: Dipartimento di Fisica, Università di Trento and BEC-INFM, I-38050 Povo, Italy and Institute of Spectroscopy, 142190 Troitsk, Moscow region, Russia.
authors.forename: G E
authors.initials: GE
authors.lastname: Astrakharchik
authors.forename: J
authors.initials: J
authors.lastname: Boronat
authors.forename: J
authors.initials: J
authors.lastname: Casulleras
authors.forename: And S
authors.initials: AS
authors.lastname: Giorgini