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Feedback effects and the self-consistent Thouless criterion of the attractive Hubbard model

K. S. D. Beach·R. J. Gooding·F. Marsiglio
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Abstract

We propose a fully microscopic theory of the anomalous normal state of the attractive Hubbard model in the low-density limit that accounts for propagator renormalization. Our analytical conclusions, which focus on the thermodynamic instabilities contained in the self-consistent equations associated with our formulation, have been verified by our comprehensive numerical study of the same equations. The resulting theory is found to contain no transitions at non-zero temperatures for all finite lattices, and we have confirmed, using our numerical studies, that this behaviour persists in the thermodynamic limit for low-dimensional systems.

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K. S. D. Beach, R. J. Gooding, F. Marsiglio. 2000-10-20. Feedback effects and the self-consistent Thouless criterion of the attractive Hubbard model. https://doi.org/10.1016/s0375-9601(01)00201-8

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