Ambient temperature measurements of the crystallographic cell parameters for oxygen deficient Ba2YCu3O7-δ prepared by gettered annealing indicate the presence of microscopic differences in the oxygen configuration at fixed δ dependent on annealing temperature. The loss of superconductivity with increasing oxygen deficiency is shown to be due to a step-like increase in length of the plane copper-apical oxygen bond, and not to the orthorhombic to tetragonal transition. The crystal structure of the 84K superconductor Bi2Sr2CaCu2O8+δ is described, as is the stabilization of 110K superconductivity via partial Pb/Bi substitution with long time annealing.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering