Pairing correlations in the cuprates: a numerical study of the three-band Hubbard model

TL;DR

This study uses advanced numerical methods to analyze pairing correlations in the three-band Hubbard model, revealing optimal conditions for high-temperature superconductivity in cuprates.

Contribution

It provides a comprehensive numerical analysis of pairing correlations in the three-band Hubbard model, highlighting the optimal charge-transfer energy for maximum Tc.

Findings

Reproduces key features of the cuprate phase diagram.

Identifies an optimal charge-transfer energy for highest Tc.

Shows dependence of pairing susceptibility on doping and temperature.

Abstract

We study the three-band Hubbard model for the copper oxide plane of the high-temperature superconducting cuprates using determinant quantum Monte Carlo and the dynamical cluster approximation (DCA) and provide a comprehensive view of the pairing correlations in this model using these methods. Specifically, we compute the pair-field susceptibility and study its dependence on temperature, doping, interaction strength, and charge-transfer energy. Using the DCA, we also solve the Bethe-Salpeter equation for the two-particle Green's function in the particle-particle channel to determine the transition temperature to the superconducting phase on smaller clusters. Our calculations reproduce many aspects of the cuprate phase diagram and indicate that there is an "optimal" value of the charge-transfer energy for the model where $T_c$ is largest. These results have implications for our understanding of superconductivity in both the cuprates and other doped charge-transfer insulators.