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A consistent description of the pairing symmetry in hole and electron doped cuprates within the two dimensional Hubbard model

Kazuhiko Kuroki·Hideo Aoki
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Abstract

Quantum Monte Carlo is used to calculate various pairing correlations of the 2D Hubbard model possessing band features experimentally observed in the cuprates. In the hole-doped case, where the Fermi level lies close to the van Hove singularities around $(0,π)$, the d$_{x^2-y^2}$ pairing correlation is selectively enhanced, while in the electron-doped case, where the singularities are far below the Fermi level and the Fermi surface runs through $(\pm π/2,\pm π/2)$, both d$_{x^2-y^2}$ and d$_{xy}$ correlations are enhanced with the latter having a $\sqrt{2}\times \sqrt{2}$ structure. The two pairing symmetries can mix to result in a nodeless gap.

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Kazuhiko Kuroki, Hideo Aoki. 1997-10-02. A consistent description of the pairing symmetry in hole and electron doped cuprates within the two dimensional Hubbard model. https://doi.org/10.1143/jpsj.67.1533

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