An Adiabatic Demagnetization Refrigerator
The cosmic microwave background (CMB) is ancient light radiation emitted during initial expansion of the universe. Theorists believe that gravity waves (like light waves, but related to gravity rather than to electricity) bounced around in the early universe and left measurable imprints on the CMB. Searching the CMB for these imprints can be done with a technique called bolometry, which works by measuring the heat that photons transfer to a superconducting wire. Because radiation background noise from instruments drops at low temperatures, colder bolometry equipment gives more precise results. Our lab, the Experimental Cosmology Group, manufactures bolometer arrays for several different CMB measurement experiments, and as such we need a variety of very powerful refrigerators in order to test and develop the next generation of bolometers. To further this end I will be constructing a new refrigeration system which will use a pulse tube refrigerator, a helium10 refrigerator, and a demagnetization refrigerator to cool wafers to 100 mK (1/10 of a degree above absolute zero) for testing.
Message to Sponsor
- Major: Physics
- Sponsor: Rose Hills
- Mentor: Adrian Lee, Physics