Does Simple Two-Dimensional Hubbard Model Account for High-Tc Superconductivity in Copper Oxides?

Takeshi Aimi; Masatoshi Imada

doi:10.1143/jpsj.76.113708

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arXiv · 0708.3416

Does Simple Two-Dimensional Hubbard Model Account for High-Tc Superconductivity in Copper Oxides?

Takeshi Aimi·Masatoshi Imada

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Abstract

We reexamine whether the essence of high-Tc superconductivity is contained in doped Hubbard models on the square lattice by using recently developed pre-projected Gaussian-basis Monte Carlo method. The superconducting correlations of the dx2-y2 wave symmetry in the ground state at distance r decays essentially as inverse cubic of r. The upper bound of the correlation at long distances estimated by this unbiased method is 0.001, indicating that recent extensions of dynamical mean-field theories and variational methods yielded at least an order of magnitude overestimates of it. The correlations are too weak for the realistic account of the cuprate high-Tc superconductivity.

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Takeshi Aimi, Masatoshi Imada. 2007-08-25. Does Simple Two-Dimensional Hubbard Model Account for High-Tc Superconductivity in Copper Oxides?. https://doi.org/10.1143/jpsj.76.113708

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