I PROPOSE TO DEVELOP KINETIC INDUCTANCE DETECTORS (KIDS) FOR FUTURE ASTROPHYSICS MISSIONS IN SPACE AT MILLIMETER WAVELENGTHS. KIDS ARE A TYPE OF NON-EQUILIBIRUM SUPERCONDUCTING PHOTON DETECTOR. AN IMPORTANT APPLICATION OF KIDS IS MEASURING THE POLARIZATION OF THE 2.7 K COSMIC MICROWAVE BACKGROUND RADIATION (CMB) FOR WHICH LARGE ARRAYS OF BACKGROUND-LIMITED DETECTORS ARE REQUIRED. KIDS HAVE MANY ADVANTAGES OVER THE TRADITIONAL SUPERCONDUCTING TRANSITION-EDGE SENSORS (TESS). FIRST THEY CAN BE EASILY MULTIPLEXED INTO LARGE ARRAYS. A PAIR OF COAXIAL LINES CAN READ OUT ~1000 DETECTORS. IN CONTRAST TESS REQUIRE READOUT WITH SQUIDS AMPLIFIERS AND HAVE ONLY REACHED A MULTIPLEXING FACTOR OF 32. SECOND KIDS HAVE A WIDE DYNAMIC RANGE COMPARED TO TESS WHICH HAVE A NARROWER DYNAMIC RANGE FOR OPTICAL LOADING. THIRD MANY KIDS DESIGNS ARE EXTREMELY SIMPLE; SOME REQUIRE ONLY ONE LITHOGRAPHIC FABRICATION STEP WHILE A TYPICAL TES REQUIRES ABOUT 20 STEPS. LAST BUT NOT LEAST KIDS PROVIDE GREATER IMMUNITY TO COSMIC RAYS THAN TESS. I WILL DEVELOP AND OPTIMIZE KIDS FOR THE LONG WAVELENGTH END OF THE CMB SPECTRUM FROM ~ 1 CM (30 GHZ) TO ~ 1 MM (300 GHZ) IN ORDER TO REMOVE ASTROPHYSICAL FOREGROUNDS. AS OF TODAY MOST KIDS HAVE BEEN OPTIMIZED FOR WAVELENGTHS SHORTER THAN 2 MM. I WILL FABRICATE AND TEST SUPERCONDUCTING THIN FILMS WITH SUPERCONDUCTING TRANSITION TEMPERATURE BETWEEN 300 MK AND 1.5 K. IN ORDER TO MINIMIZE THE NOISE FROM THERMALLY-GENERATED QUASIPARTICLES THE DETECTORS WILL BE OPERATED AT AT TEMPERATURE WELL BELOW THE TRANSITION TEMPERATURE IN A CRYOGENIC TEST FACILITY AT UW-MADISON WHICH CAN ACHIEVE TEMPERATURE AS LOW AS 100 MK. I WILL ALSO INVESTIGATE THE NOISE PERFORMANCE OF KIDS BASED ON AN EXISTING ELECTROTHERMAL MODEL AND COMPARE OUR MEASUREMENTS TO THE MODEL. THE ULTIMATE GOAL IS TO OPTIMIZE THE KIDS DEVICES WHILE MINIMIZING THE NOISE GIVEN THE CONSTRAINS FROM THE CRYOGENIC SYSTEM THIS PROPOSAL ADDRESSES OBJECTIVE 1.6 OF NASA'S STRATEGIC PLAN: DISCOVER HOW THE UNIVERSE WORKS EXPLORE HOW IT BEGAN AND EVOLVED AND SEARCH FOR LIFE ON PLANETS AROUND OTHER STARS. WITHIN NASA'S ASTROPHYSICS PROGRAM IT BELONGS TO THE 'PHYSICS OF THE COSMOS' THEME: TO DISCOVER HOW THE UNIVERSE WORKS AT THE MOST FUNDAMENTAL LEVEL INCLUDING THE FORCES WHICH DROVE THE BIG BANG AND CONTINUE TO DRIVE THE ACCELERATED EXPANSION OF THE UNIVERSE. . IT ALSO BELONGS TO THE 'RESEARCH ANALYSIS AND TECHNOLOGY DEVELOPMENT' THEME SPECIFICALLY DETECTOR TECHNOLOGY DEVELOPMENT. THE DETECTORS I DEVELOP WILL BE PARTICULARLY USEFUL FOR FUTURE NASA MISSIONS TO MEASURE THE CMB POLARIZATION SUCH AS RECENTLY PROPOSED MISSIONS LIKE LITEBIRD PIXIE CORE AND CMBPROBE.
$118,474FY2020National Aeronautics and Space AdministrationNASA
University Of Wisconsin System, Madison WI