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Stripes and superconducting pairing in the t-J model with Coulomb interactions

E. Arrigoni·A. P. Harju·W. Hanke·B. Brendel·S. A. Kivelson
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Abstract

We study the competition between long- and short-range interactions among charge carriers in strongly-correlated electronic systems employing a new method which combines the density-matrix renormalization-group technique with a self-consistent treatment of the long-range interactions. We apply the method to an extended t-J model which exhibits ``stripe'' order. The Coulomb interactions, while not destroying stripes, induce large transverse stripe fluctuations with associated charge delocalization. This leads to a substantial Coulomb-repulsion-induced {\it enhancement} of long-range superconducting pair-field correlations.

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E. Arrigoni, A. P. Harju, W. Hanke, B. Brendel, S. A. Kivelson. 2001-10-16. Stripes and superconducting pairing in the t-J model with Coulomb interactions. https://doi.org/10.1103/physrevb.65.134503

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