The ‘magic’ electronic state of high-Tc cuprate superconductors

Abstract

The available experimental data for 105 distinct families of high-T(c) oxocuprate superconductors point to the presence of a 'magic' intrasheet Cu-O separation of 1.923 A, which yields the highest T(c) values at ambient pressure (Rao 1995). The interpretation with Burdett's model (1993), along with electronic band structure calculations, is centered at a crossing of the O- and Cu-predominated sigma bands and points to the significance of the electron-phonon coupling for these materials.