Physical Sciences and Mathematics Commons^™

Effect Of Long-Range Hopping On Tc In A Two-Dimensional Hubbard-Holstein Model Of The Cuprates, Ehsan Khatami, A. Macridin, M. Jarrell

Faculty Publications

We study the effect of long-range hoppings on Tc for the two-dimensional (2D) Hubbard model with and without Holstein phonons using parameters evaluated from band-structure calculations for cuprates. Employing the dynamical cluster approximation (DCA) with a quantum Monte Carlo (QMC) cluster solver for a 4-site cluster, we observe that without phonons, the long-range hoppings, t′ and t′′, generally suppress Tc. We argue that this trend remains valid for larger clusters. In the presence of the Holstein phonons, a finite t′ enhances Tc in the under-doped region for the hole-doped system, consistent with local-density approximation (LDA) calculations and experiment. This is …