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Superconductivity in the two-dimensional Hubbard model?

D. Baeriswyl·D. Eichenberger·B. Gut
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Abstract

A refined variational wave function for the two-dimensional repulsive Hubbard model is studied numerically, with the aim of approaching the difficult crossover regime of intermediate values of U. The issue of a superconducting ground state with d-wave symmetry is investigated for an average electron density n=0.8125 and for U=8t. Due to finite-size effects a clear-cut answer to this fundamental question has not yet been reached.

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D. Baeriswyl, D. Eichenberger, B. Gut. 2006-12-29. Superconductivity in the two-dimensional Hubbard model?. https://doi.org/10.1002/pssb.200674601

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