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arXiv:cond-mat/0009433 · Physical review. B, Condensed matter

Pairing, charge, and spin correlations in the three-band Hubbard model

Zhongbing Huang, Hua Lin, James E. Gubernatis

Published Mar 1, 2001• 28 citations
arXivHTMLPDF

Abstract

Using the constrained path Monte Carlo method, we simulated the two-dimensional, three-band Hubbard model to study pairing, charge, and spin correlations as a function of electron and hole doping and the Coulomb repulsion ${V}_{\mathrm{pd}}$ between charges on neighboring Cu and O lattice sites. As a function of distance, both the ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$-wave and extended s-wave pairing correlations decayed quickly. In the charge-transfer regime, increasing ${V}_{\mathrm{pd}}$ decreased the long-range part of the correlation functions in both channels, while in the mixed-valent regime, it increased the long-range part of the s-wave behavior but decreased that of the d-wave behavior. Still the d-wave behavior dominated. At a given doping, increasing ${V}_{\mathrm{pd}}$ increased the spin-spin correlations in the charge-transfer regime but decreased them in the mixed-valent regime. Also, increasing ${V}_{\mathrm{pd}}$ suppressed the charge-charge correlations between neighboring Cu and O sites. Electron and hole doping away from half-filling was accompanied by a rapid suppression of antiferromagnetic correlations. Our results suggest that adding a repulsive ${V}_{\mathrm{pd}}$ to the model does not enhance its tendency toward superconductivity even though the behavior of the spin structure factor is consistent with the properties of some high-temperature superconducting materials.

DOI
10.1103/physrevb.63.115112

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