Superconductivity in the three-band model of cuprates: nodal direction characteristics and influence of intersite interactions

TL;DR

This paper uses the three-band Emery model with advanced correlation techniques to analyze key features of d-wave superconductivity in cuprates, examining the effects of intersite interactions and comparing results with experiments.

Contribution

It introduces a detailed analysis of the three-band model incorporating intersite interactions and correlation effects, providing insights into the superconducting properties of cuprates.

Findings

Nodal Fermi velocity and effective mass agree with experimental data.

Next-nearest neighbor hopping influences superconducting phase.

Intersite Coulomb repulsion impacts superconductivity characteristics.

Abstract

The three-band Emery model is applied to study the selected principal features of the $d$-$wave$ superconducting phase in the copper-based compounds. The electron-electron correlations are taken into account by the use of the diagrammatic expansion of the Guztwiller wave function (DE-GWF) method. The nodal Fermi velocity, Fermi momentum and effective mass are all determined in the paired state and show relatively good agreement with the available experimental data, as well as with the corresponding single-band calculations. Additionally, the influence of the next-nearest neighbor oxygen-oxygen hopping and intersite Coulomb repulsion terms on the superconducting phase is analyzed.