In-Plane Oxygens in High-Temperature Superconducting Cuprates

Abstract

The role of the oxygen degree of freedom in the cuprates' superconducting planes is analyzed in detail. Structural and photoemission results are reviewed to show that the most sparse description of the in-plane electronic states requires explicit control of the oxygens. For metallic states, the relative contributions of oxygen and copper vary along the Fermi surface (FS), with the arc metallicity dominantly oxygen-derived. For the magnetic responses, we find that the observed incommensurability arises naturally if one keeps separate the roles of the two sites. For the charge order in LBCO, we propose a scenario, based on magnetic interactions in the plane. We stress the need for further experimental investigations of the evolution of the intracell charge distribution with doping, and for a better theoretical understanding of the large particle-hole-symmetry breaking required for successful phenomenologies, but difficult to reconcile with ab initio calculations.

Fundamental Building Blocks of Strongly Correlated Wave Functions

“…In cuprates at least, the experimental evidence points to a separation of roles between the electrons occupying copper and oxygen orbitals, such that, roughly speaking, the coppers are responsible for the local, and the oxygens for the extended degrees of freedom [4]. Because of strong Cu-O hybridization, this separation is partly a dynamical phenomenon [5], and partly produces real-space disorder [6,7,8].…”