Professor John R. Clem passed away on August 2, 2013 at his home in Ames, Iowa after a four-year battle with mesothelioma. John was born on April 24, 1938 in Waukegan, Illinois; his parents were trained as teachers. John received scholarships at the University of Illinois, where he received his undergraduate degree in engineering physics. John was a last graduate student of John Bardeen and earned his Ph.D. in superconductivity under his supervision. After postdoctoral appointments in Maryland and Münich, John joined the Iowa State University Physics Department and The Ames Laboratory in 1967, and enjoyed 46 years of productive collaboration with ISU and Ames Lab colleagues. For the community of people dealing with a broad field of type-II superconductivity, John's name is and will always be associated with such hits as 'pancake vortices', the term coined by John soon after the discovery of layered high-Tc cuprate superconductors. John established and edited the tremendously successful and useful “High-Tc Update” from 1987 to 2000, well remembered by all participants in the high-Tc boom. Among many other contributions to superconducting phenomenology, John’s papers on ac losses, edge pinning, flux-cutting, and recently on critical currents in superconducting thin-film strips of various shapes – a hot topic in superconducting electronics – will be remembered and cited in years to come. His last paper, still under review in Physical Review B at the day of his death, deals with a century-old problem of the structure of the intermediate state in type-I superconductors. John was also an avid vocalist, who enjoyed singing baritone at many occasions, conference banquets included. John is survived by his wife, Judy Clem, sister, Caryl Clem, children, Paul Clem and Jean (Clem) Latzke, and three grandchildren.
