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Dynamical mean-field theory for pairing and spin gap in the attractive Hubbard model

M. Keller·W. Metzner·U. Schollwoeck
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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 quasi-particle weight vanishes discontinuously at the transition between the two normal states.

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M. Keller, W. Metzner, U. Schollwoeck. 2001-01-04. Dynamical mean-field theory for pairing and spin gap in the attractive Hubbard model. https://doi.org/10.1103/physrevlett.86.4612

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