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Attractive Hubbard model and single-particle pseudogap due to classical pairing fluctuations in two dimensions

Y. M. Vilk·S. Allen·H. Touchette·S. Moukouri·L. Chen·A. -M. S. Tremblay
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Abstract

It is shown that in the two-dimensional attractive Hubbard model, the mean-field phase transition is replaced by a renormalized classical regime of fluctuations where a pseudogap opens up in the single-particle spectral weight. It is argued that this pseudogap and precursors of the ordered state quasiparticles can occur only in strongly anisotropic quasi two-dimensional materials. This precursor phenomenon differs from preformed local pairs. Furthermore, while critical antiferromagnetic fluctuations would also lead to a pseudogap in the repulsive model, there are some important differences between the superconducting and magnetic pseudogap.

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Y. M. Vilk, S. Allen, H. Touchette, S. Moukouri, L. Chen, A. -M. S. Tremblay. 1999-02-08. Attractive Hubbard model and single-particle pseudogap due to classical pairing fluctuations in two dimensions. https://doi.org/10.1016/s0022-3697(98)00129-2

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