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Pairing Correlations on t-U-J Ladders

S. Daul·D. J. Scalapino·Steven R. White
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Abstract

Pairing correlations on generalized t-U-J two-leg ladders are reported. We find that the pairing correlations on the usual t-U Hubbard ladder are significantly enhanced by the addition of a nearest-neighbor exchange interaction J. Likewise, these correlations are also enhanced for the t-J model when the onsite Coulomb interaction is reduced from infinity. Moreover, the pairing correlations are larger on a t-U-J ladder than on a t-Jeff ladder in which Jeff has been adjusted so that the two models have the same spin gap at half-filling. This enhancement of the pairing correlations is associated with an increase in the pair-binding energy and the pair mobility in the t-U-J model and point to the importance of the charge transfer nature of the cuprate systems.

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S. Daul, D. J. Scalapino, Steven R. White. 1999-11-17. Pairing Correlations on t-U-J Ladders. https://doi.org/10.1103/physrevlett.84.4188

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