 Dehmelt became an assistant professor at the University of Washington in Seattle, Washington in 1955, an associate professor in 1958, and a full professor in 1961.In 1955 he built his first electron impact tube in George Volkoff's laboratory at the University of British Columbia and experimented on paramagnetic resonances in polarized atoms and free electrons.In the 1960s, Dehmelt and his students worked on spectroscopy of hydrogen and helium ions.