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arXiv:cond-mat/9411064 · Physical review. B, Condensed matter

Superconductivity in an exactly solvable Hubbard model with bond-charge interaction

Andreas Schadschneider

Published Apr 15, 1995• 83 citations
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Abstract

The Hubbard model with an additional bond-charge interaction X is solved exactly in one dimension for the case t=X, where t is the hopping amplitude. In this case the number of doubly occupied sites is conserved. In the sector with no double occupations the model reduces to the U=\ensuremath{\infty} Hubbard model. In arbitrary dimensions the qualitative form of the phase diagram is obtained. It is shown that for moderate Hubbard interactions U the model has superconducting ground states.

DOI
10.1103/physrevb.51.10386

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The Hubbard model with an additional bond-charge interaction X is solved exactly in one dimension for the case t=X, where t is the hopping amplitude. In this case the number of doubly occupied sites is conserved. In the sector with no double occupations the model reduces to the U=\ensuremath{\infty} Hubbard model. In arbitrary dimensions the qualitative form of the phase diagram is obtained. It is shown that for moderate Hubbard interactions U the model has superconducting ground states.
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