INFRARED DETECTORS USING HIGH CRITICAL TEMPERATURE GRANULAR JOSEPHSON JUNCTIONS

THE RECENT DISCOVERY OF HIGH TEMPERATURE SUPERCONDUCTING MATERIALS HAS LED TO RENEWED INTEREST IN THE APPLICATION OF SUPERCONDUCTIVITY. THE NEW CERAMIC SUPERCONDUCTORS OFFER THE OPPORTUNITY OF USING THESE MATERIALS AS DETECTORS OF INFRARED RADIATION MORE CONVENIENTLY THAT THE OLDER, CLASSICAL SUPERCONDUCTORS. THE LARGER ENERGY GAP OF THESE NEW HIGH CRITICAL TEMPERATURE (T(C)) MATERIALS ALSO PROVIDES THE OPPORTUNITY TO FABRICATE JOSEPHSON JUNCTION (JJ) DETECTORS CAPABLE OF SENSING RADIATION AT MUCH SHORTER WAVELENGTHS, OFFERING NEW COMPETITION TO PREVIOUS SEMICONDUCTOR IR DETECTORS IN THE 10 TO 100 MUM REGION. RECENT WORK HAS DEMONSTRATED THAT GRANULAR SUPERCONDUCTORS SHOW WIDE-BAND SENSITIVITY TO RADIATION. THE OBJECTIVE OF THE PRESENT PROJECT IS TO USE THE NEW TECHNOLOGY IN MAKING THIN FILMS OF THESE GRANULAR SUPERCONDUCTORS TO DEVELOP IR SENSORS BASED ON THESE EFFECTS. THE APPROACH IN PHASE I IS TO USE FILMS OF THE YBACUO AND BICUBASR MATERIALS (AND POSSIBILY OTHERS) TO DEMONSTRATE THE FEASIBILITY OF THESE MATERIALS AS IR DETECTORS.