Predictions for structural stability and electronic evolution in pressure-induced overdoped YBa2Cu3O7

Abstract

The electronic evolution in the entire overdoped region of cuprates has never been accessed, though the clarification of this evolution should help to refine the crucial physical arguments in producing the superconductivity. Motivated by uncovering this, we performed first-principles calculations and molecular dynamics simulations for the pressure-induced overdoped YBa2Cu3O7. The mechanical and dynamic stability of orthorhombic YBa2Cu3O7 lays the foundation of exploration for the electronic evolution. We found that no transition of semiconducting state was identified and similar Fermi surfaces still exist in the entire overdoped region. The role of charge density at CuO2 plane was also discussed. Moreover, based on the analysis of BCS picture, we recommended that the electron-phonon regime is not prominently responsible for the Tc, and the evolution of N(EF) or the position of Van Hove singularity (VHs), i.e., EF-EVHs, may direct an alternative way instead to uncover the superconductivity of YBa2Cu3O7 category if the BCS picture is taken.