Bound states in the phase diagram of the extended Hubbard model

TL;DR

This paper investigates how exact two-electron bound state results influence the phase diagram of the extended Hubbard model, revealing suppression of superconductivity at low electron densities.

Contribution

It demonstrates the impact of known bound states on the phase diagram, especially the suppression of superconductivity at small charge densities.

Findings

Superconducting state is suppressed at low charge densities.

Bound states significantly alter the phase diagram.

Normal phase becomes dominant at small densities.

Abstract

The papaer shows how the known, exact results for the two electron bound states can modify the ground state phase diagram of extended Hubbard model (EHM) for on-site attraction, intersite repulsion and arbitrary electron density. The main result is suppression of the superconducting state in favor of normal phase for small charge densities.