Reexamination of d-wave superconductivity in the two-dimensional Hubbard model

Takao Morinari

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Reexamination of d-wave superconductivity in the two-dimensional Hubbard model

Takao Morinari

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Abstract

We reexamine the possibility of d-wave superconductivity in the hole-doped two-dimensional Hubbard model. In terms of the gauge field description of the spin fluctuations, we show that d-wave superconductivity is unstable in the perturbative region with respect to the on-site Coulomb repulsion, U. Whereas in the region where d-wave superconductivity is possible, there is a strong constraint on the gap of superconductivity. Analysis of the localized spin moments suggests that there is another d-wave (d_{x^2-y^2}-wave) pairing due to the short-range antiferromagnetic correlation.

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Takao Morinari. 2002-01-05. Reexamination of d-wave superconductivity in the two-dimensional Hubbard model. https://arxiv.org/abs/cond-mat/0201058

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