Combined density functional and dynamical cluster quantum Monte Carlo calculations of the three-band Hubbard model for hole-doped cuprate superconductors

Using a combined local density functional theory (DFT-LDA) and quantum Monte Carlo (QMC) dynamic cluster approximation approach, the parameter dependence of the superconducting transition temperature Tc of several single-layer hole-doped cuprate superconductors with experimentally very different Tcmax is investigated. The parameters of two different three-band Hubbard models are obtained using the LDA and the downfolding N th-order muffin-tin orbital technique with N=0 and 1, respectively. QMC calculations on four-site clusters show that the d -wave transition temperature Tc depends sensitively on the parameters. While the N=1MTO basis set which reproduces all three pdσ bands leads to a d -wave transition, the N=0 set which merely reproduces the LDA Fermi surface and velocities does not.