Anisotropic dressing of electrons in electron-doped cuprate superconductors

TL;DR

This paper explores the similarities in phase diagrams of electron- and hole-doped cuprate superconductors, focusing on anisotropic electron dressing and its effects on electronic structure and spectral features.

Contribution

It introduces a kinetic-energy driven superconductivity model to explain the anisotropic dressing and Fermi surface features in electron-doped cuprates, highlighting their resemblance to hole-doped counterparts.

Findings

Electron Fermi surface is truncated into Fermi arcs.

Dip in peak-dip-hump structure correlates with scattering rate peaks.

Dispersion kink is linked to inflection points in self-energy.

Abstract

The recent experiments revealed a remarkable possibility for the absence of the disparity between the phase diagrams of the electron- and hole-doped cuprate superconductors, while such an aspect should be also reflected in the dressing of the electrons. Here the phase diagram of the electron-doped cuprate superconductors and the related exotic features of the anisotropic dressing of the electrons are studied based on the kinetic-energy driven superconductivity. It is shown that although the optimized Tc in the electron-doped side is much smaller than that in the hole-doped case, the electron- and hole-doped cuprate superconductors rather resemble each other in the doping range of the superconducting dome, indicating an absence of the disparity between the phase diagrams of the electron- and hole-doped cuprate superconductors. In particular, the anisotropic dressing of the electrons due to the strong electron's coupling to a strongly dispersive spin excitation leads to that the electron Fermi surface is truncated to form the disconnected Fermi arcs centered around the nodal region. Concomitantly, the dip in the peak-dip-hump structure of the quasiparticle excitation spectrum is directly associated with the corresponding peak in the quasiparticle scattering rate, while the dispersion kink is always accompanied by the corresponding inflection point in the total self-energy, as the dip in the peak-dip-hump structure and dispersion kink in the hole-doped counterparts. The theory also predicts that both the normal and anomalous self-energies exhibit the well-pronounced low-energy peak-structures.