We study the competition between long- and short-range interactions among charge carriers in strongly-correlated electronic systems employing a 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 enhancement of long-range superconducting pair-field correlations.

• Received 17 October 2001

DOI:https://doi.org/10.1103/PhysRevB.65.134503