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arXiv · 2607.21478

Pseudogap formation in the moderate correlated layered attractive Hubbard model

A. V. Belov·A. N. Rubtsov·B. Krippa
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Abstract

We consider the layered attractive Hubbard model with a moderate interaction strength at quarter filling. The Green's function, self-energy, and density of states are calculated for relatively large clusters using the fluctuating local field method within the approximation of vanishing effective interaction. The emergence of a pseudogap is demonstrated for the cluster system, and it is shown that integration over the fluctuating field is equivalent to the summation of zero-mode ladder diagrams above critical temperature. For the large layered system, a pseudogap in the density of states is obtained within a cluster scheme that treats the coupling between layers as a static $U(1)$ symmetry-breaking field.

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A. V. Belov, A. N. Rubtsov, B. Krippa. 2026-07-23. Pseudogap formation in the moderate correlated layered attractive Hubbard model. https://arxiv.org/abs/2607.21478

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