title: Dynamical mean-field theory for pairing and spin gap in the attractive hubbard model.
abstract: We solve the attractive Hubbard model for arbitrary interaction strengths within dynamical mean-field theory. We compute the transition temperature for superconductivity and analyze electron pairing in the normal phase. The normal state is a Fermi liquid at weak coupling and a non-Fermi-liquid state with a spin gap at strong coupling. Away from half filling, the quasiparticle weight vanishes discontinuously at the transition between the two normal states.
authors.affiliation: Theoretische Physik C, Technische Hochschule Aachen, D-52056 Aachen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Keller
authors.forename: W
authors.initials: W
authors.lastname: Metzner
authors.forename: U
authors.initials: U
authors.lastname: Schollwöck