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Overscreening in Hubbard electron systems

H. -B. Schüttler·C. Gröber·H. G. Evertz·W. Hanke
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Abstract

We show that doping-induced charge fluctuations in strongly correlated Hubbard electron systems near the 1/2-filled, insulating limit cause overscreening of the electron-electron Coulomb repulsion. The resulting attractive screened interaction potential supports d_{x^2-y^2}-pairing with a strongly peaked, doping dependent pairing strength at lower doping, followed by s-wave pairing at larger doping levels.

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H. -B. Schüttler, C. Gröber, H. G. Evertz, W. Hanke. 1998-05-12. Overscreening in Hubbard electron systems. https://arxiv.org/abs/cond-mat/9805133

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