High temperature superconductivity and charge segregation in a model with strong long-range electron-phonon and Coulomb interactions

Abstract

An analytical method of studying strong long-range electron-phonon and Coulomb interactions in complex lattices is presented. The method is applied to a perovskite layer with anisotropic coupling of holes to the vibrations of apical atoms. Depending on the relative strength of the polaronic shift, Ep, and the inter-site Coulomb repulsion, Vc, the system is either a polaronic Fermi liquid, Vc > 1.23 Ep, a bipolaronic superconductor, 1.16 Ep < Vc < 1.23 Ep, or a charge segregated insulator, Vc < 1.16 Ep. In the superconducting window, the carriers are mobile bipolarons with a remarkably low effective mass. The model describes the key features of the underdoped superconducting cuprates.

5 pages, 2 figures (1 color)

References in corpus (2)

• Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors
• Bipolarons in the Extended Holstein Hubbard Model

Cited by in corpus (6)

• Effect of Electron-Phonon Interaction Range for a Half-Filled Band in One Dimension
• Enhanced stability of bound pairs at nonzero lattice momenta
• Two-particle bound states on a lattice
• Relaxation timescales and electron-phonon coupling in optically-pumped YBa${}_2$Cu${}_3$O${}_{6+x}$ revealed by time-resolved Raman scattering
• Mass of a lattice polaron from extended Holstein model using Yukawa potential
• Stable pair liquid phase in fermionic systems