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 T-c of several single-layer hole-doped cuprate superconductors with experimentally very different T-c max is investigated. The parameters of two different three-band Hubbard models are obtained using the LDA and the downfolding Nth-order muffin-tin orbital technique with N=0 and 1, respectively. QMC calculations on four-site clusters show that the d-wave transition temperature T-c depends sensitively on the parameters. While the N=1 MTO basis set which reproduces all three pd sigma bands leads to a d-wave transition, the N=0 set which merely reproduces the LDA Fermi surface and velocities does not.