HMC Physics Colloquium
Tuesdays at 16:30 in Shanahan Center for Teaching and Learning, Room B460
University of California at Berkeley
March 7, 2006
Applications of SQUIDs-ranging from geophysics to quantum computing-are briefly reviewed. Two other applications are discussed in more detail. The first is for cosmology, in a search for galaxy clusters, looking for tiny deviations of the cosmic background radiation from the Planck distribution. The electromagnetic radiation is detected by a bolometer consisting of a superconducting transition-edge sensor coupled to a SQUID amplifier. An array of 330 such detectors is about to be fielded on a telescope at Atacama, Chile. The second application is concerned with nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) in magnetic fields of about 10-4 T, comparable to the Earth’s field and four orders of magnitude lower than that used in conventional MRI. Images of phantoms and of the human forearm are presented, enhanced contrast due to weighting by the longitudinal relaxation time is illustrated, and the ability to obtain undistorted images in the presence of metals is demonstrated. Potential clinical applications are discussed.