THE PROPOSED RESEARCH WILL INVESTIGATE THE FEASIBILITY OF OPERATING CRYOGENIC BOLOMETERS IN AN INTEGRATING MODE.

THE PROPOSED RESEARCH WILL INVESTIGATE THE FEASIBILITY OF OPERATING CRYOGENIC BOLOMETERS IN AN INTEGRATING MODE. THISNOVEL DEVICE PROMISES DRAMATIC IMPROVEMENTS IN THE NOISE EQUIVALENT POWER AND COOLING REQUIREMENTS OF ULTRA HIGH SENSITIVITY FAR INFRARED SYSTEMS, BOTH FOR DISCRETE APPLICATIONS AND ARRAY CONCEPTS. THE CONCEPT INVOLVES THE USE OF THIN SUPERCONDUCTING FILMS TO ACT AS BOTH ELECTRICAL CONDUCTORS AND AS A HEAT SWITCH BETWEEN THE BOLOMETRIC ELEMENT AND THE COOLING BATH. THE BOLOMETERS ARE SWITCHED BETWEEN THE INTEGRATING STATE (LOW THERMAL CONDUCTIVITY) ANDTHE RESET STATE ( HIGH THERMAL CONDUCTIVITY) USING AN EXTERNAL MAGNETIC FIELD. FOR TYPE 1 SUPERCONDUCTORS SUCH ASINDIUM, THE CRITICAL FIELD CAN BE AS LOW AS 0.03 TESLA. AT TEMPERATURES OF 0.3 K, THE DIFFERENCE IN THERMAL CONDUCTIVITY BETWEEN THE TWO STATES CAN BE GREATER THAN 100,YIELDING A POTENTIAL GAIN IN SENSITIVITY OF 10 OVER A CONVENTIONAL DESIGN. IN THE PROPOSED RESEARCH WE WILL EXPERIMENTALLY INVESTIGATE THE THERMAL AND MAGNETIC PROPERTIES OF SUPERCONDUCTING FILMS IN A BOLOMETER CONFIGURATION AND PRODUCE A BASIC DESIGN FOR SUCH A DEVICE.