David Gidley
Professor Gidley has performed precision measurements of the singlet and triplet annihilation decay rates of the particle-antiparticle system called positronium. Comparison with calculations of these decay rates comprises a unique test of quantum electrodynamics. He has searched for exotic positronium decay modes as tests of fundamental conservation laws and discrete symmetries. His positron studies of metal surfaces and thin films include surface defects, film growth, and the generation and polarimetry of spin polarized low energy positron beams to probe surface magnetism.
Professor Gidley is also using low energy positron beams to depth-profile surface, interface, and thin film properties of polymers, nanocomposites, and bulk metallic glasses. His group is actively working with a host of industrial partners to develop a new positronium probe of nanoporous thin films. Such materials with engineered porosity at the nanometer scale are being intensely pursued by the microelectronics industry as next generation dielectrics in high-speed devices.
His group is collaborating with NC State to construct a high rate positron beam center for nanoporosity characterization at the nuclear reactor in Raleigh NC.