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Superconductivity with angular dependent coupling: stripes, Coulomb repulsion and enhanced Tc

V. V. Moshchalkov·V. A. Ivanov
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Abstract

We have analysed the effect of intrinsic doping inhomogeneity and the presence of stripes in high-T_c superconductors on coupling λby using a simple analytically solvable model with an angular dependent λ(ϕ) represented by a square-well form. We have found that the introduction of the Coulomb repulsion λ_C, increasing the ''contrast'' | λ| + | λ_C |, or the depth of the angular modulation of λ(ϕ), leads to a remarkable enhancement of T_c. This effect can be optimized by combining attractive (λ<0) and repulsive (λ>0) interactions along stripes and perpendicular to them.

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V. V. Moshchalkov, V. A. Ivanov. 1999-12-06. Superconductivity with angular dependent coupling: stripes, Coulomb repulsion and enhanced Tc. https://arxiv.org/abs/cond-mat/9912091

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