John R. Clem
The goal of my current research program has been to make significant theoretical advances con cerning the electrodynamic behavior of current-carrying superconductors subjected to mag netic fields. Recently I have been giving greatest attention to the high-temperature superconduc tors, first discovered in 1986. Problems that I am particularly interested in include flux pinning, critical currents, flux flow, ac losses, noise, spiral and intersecting vortices, instabilities, surface and interface effects, proximity effects, and two- and three-dimensional arrays of Josephson junctions. Although my focus is generally on the solution of fundamental problems, I always have been strongly motivated by the fact that a solidly based theoretical understanding of the above interrelated subjects is needed to make the most effective use of superconductors in various applications, both large-scale (e.g., wire and tapes for high-field magnets and power transmission lines) and small-scale (e.g., filters, resonators, and Josephson devices for use in sensitive detectors and logic devices.)
(Chronologically most recent on top)Education
- Ph.D. Physics, University of Illinois, 1965
- M.S. Physics, University of Illinois, 1962
- B.S. Engineering Physics, University of Illinois, 1960
(Chronologically most recent on top)Professional Appointments
- 2001 - 2010 Contract Associate (1/4 time), Ames Laboratory
- 1992 - 1993 Visiting Scientist, Electric Power Research Institute, Palo Alto, CA
- 1992 - 1993 Visiting Professor of Applied Physics, Stanford University, Stanford, CA
- 1985 - 1986 Visiting Scientist, IBM Thomas J. Watson Research Center, Yorktown Heights, NY
- 1982 - 1985 Chairman, Department of Physics, Iowa State University
- 1975 - 2001 Senior Physicist, Ames Laboratory
- 1974 - 1975 Fulbright Research Fellow, Kernforschungsanlage Jülich, Germany
- 1971 - 2010 Various appointments as Consultant at Los Alamos National Laboratory, Argonne National Laboratory, Brookhaven National Laboratory, IBM Thomas J. Watson Research Center, Allied-Signal Aerospace Company, Underground Systems, Inc., American Superconductor Corporation, Pirelli Cable Corporation
- 1970 - 1975 Physicist, Ames Laboratory
- 1967 - 1970 Associate Physicist, Ames Laboratory
- 1966 - 1967 Visiting Research Fellow, Technical University, Munich, Germany
- 1965 - 1966 Research Associate, University of Maryland
(Chronologically most recent on top)Honors & Awards
- 2010 American Physical Society Outstanding Referee
- 2004 Fellow, Institute of Physics, London
- 1999 Most Valuable Instructor (teaching award from graduate students in the Iowa State University Department of Physics and Astronomy, 2000)
- 1997 Phi Kappa Phi Centennial Medalist, Iowa State University Chapter of Phi Kappa Phi
- 1991 Teaching Award from Graduate Students in the Iowa State University Department of Physics and Astronomy
- 1990 For contributions to the superconductivity community, Applied Superconductivity Conference, Inc.
- 1988 DOE Annual Award for Sustained Outstanding Research in Solid State Physics
- American Association of University Professors
- 1982 Fellow, American Physical Society
(Chronologically most recent on top)Publications with the Ames Laboratory
Connolly M R; Milosevic M V; Bending S J; Clem J R; Tamegai T . 2009. Continuum vs. discrete flux behaviour in large mesoscopic Bi2Sr2CaCu2O8+delta disks. Epl. 85:17008.
Kuit K H; Kirtley J R; van der Veur W; Molenaar C G; Roesthuis F J G; Troeman A G P; Clem J R; Hilgenkamp H; Rogalla H; Flokstra J . 2008. Vortex trapping and expulsion in thin-film YBa2Cu3O7-delta strips. Physical Review B. 77:134504.
Clem J . 2008. Geometrical Barriers and the Growth of Flux Domes in Thin Ideal Superconducting Disks. Journal of Superconductivity and Novel Magnetism. 21:343-352.
Clem J R; Claassen J H; Mawatari Y . 2007. AC losses in a finite Z stack using an anisotropic homogeneous-medium approximation. Superconductor Science & Technology. 20:1130-1139.