SQUID Susceptometers for Read Out of Magnetic Microcalorimeters--Hypres, Inc., 175 Clearbrook Road, Elmsford, NY 10523-1109; 914-592-1190
Dr. Masoud Radparvar, Principal Investigator
Dr. Elie Track, Business Official
DOE Grant No. DE-FG02-99ER82800
Amount: $749,974

A magnetic calorimeter is an attractive candidate for an x-ray detector for nuclear physics research. This project will develop an array of magnetic microcalorimeters based upon the use of magnetic sensors to measure very small temperature changes resulting from the absorption of x-rays in a telescope. The mag-netization of localized paramagnetic ions in a metallic matrix will be determined by using a DC Superconducting Quantum Interference Device (SQUID), which is extremely sensitive and ideally adapted to the measurement of flux changes. The resultant sensitivity of this calorimeter will be only weakly dependent upon heat capacity and should exhibit a very fast response. In Phase I, a new fabrication process was developed, and ultra-low SQUID susceptometers were designed, fabricated, and integrated with magnetic microcalorimeters for x-ray measurements. In Phase II, an array of magnetic microcalorimeters will be developed and integrated with an array of these SQUID susceptometers. The goal is to demonstrate a complete imaging system with resolution of 2 ev at 6 keV for the focal plane of an x-ray telescope.

Commercial Applications and Other Benefits as described by the awardee: The availability of a magnetic microcalorimeter, integrated with a low-cost SQUID susceptometer, should have many nuclear and high energy physics research applications. In addition, the SQUID readout can be used for biomagnetometry for the mapping of brain functions, and the detection of corrosion and cracks in aircraft.