INTERFACIAL La-Ba-Cu-O TYPE SUPERCONDUCTING THIN FILMS
Original Publication Date: 1989-Jun-01
Included in the Prior Art Database: 2005-Jan-28
The La-Ba-Cu-O type superconductors discovered by Bednorz and Muller are made up of planes of CuO6 octahedra sharing corners with the CuO6 planes separated by (La,Ba)-O layers within which the La and Sr are nine-fold coordinated to oxygen. The Cu-O bonding is very distorted, with the Cu assuming a planar four-fold coordination with oxygen. Substitution of Ba (or Sr) for La in small amounts oxidizes some of the Cu to Cu3+ and results in a mixed valence compound and modifies the superconducting transition temperature.