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Pair fluctuation induced pseudogap in the normal phase of the two-dimensional attractive Hubbard model at weak coupling

Daniel Rohe·Walter Metzner
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Abstract

One-particle spectral properties in the normal phase of the two-dimensional attractive Hubbard model are investigated in the weak coupling regime using the non-selfconsistent T-matrix approximation. The corresponding equations are evaluated numerically directly on the real frequency axis. For temperatures sufficiently close to the superconducting transition temperature a pseudogap in the one-particle spectral function is observed, which can be assigned to the increasing importance of pair fluctuations.

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Daniel Rohe, Walter Metzner. 2001-03-07. Pair fluctuation induced pseudogap in the normal phase of the two-dimensional attractive Hubbard model at weak coupling. https://doi.org/10.1103/physrevb.63.224509

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