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Magnetic and superconducting correlations in the two-dimensional Hubbard model

W. Metzner·J. Reiss·D. Rohe
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Abstract

The interplay and competition of magnetic and superconducting correlations in the weakly interacting two-dimensional Hubbard Model is investigated by means of the functional renormalization group. At zero temperature the flow of interactions in one-loop approximation evolves into a strong coupling regime at low energy scales, signalling the possible onset of spontaneous symmetry breaking. This is further analyzed by a mean-field treatment of the strong renormalized interactions which takes into account magnetic and superconducting order simultaneously. The effect of strong correlations on single-particle properties in the normal phase is studied by calculating the flow of the self-energy.

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W. Metzner, J. Reiss, D. Rohe. 2005-09-15. Magnetic and superconducting correlations in the two-dimensional Hubbard model. https://doi.org/10.1002/pssb.200562445

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