C. Peter Flynn
professor of Physics and of Materials Science and Engineering
Professor Flynn received his bachelor's degree and Ph.D. in physics from the University of Leeds in 1957 and 1960, respectively. He subsequently earned an M.A. (Hon.) in physics from the University of Cambridge. He came to the University of Illinois in 1960 as a research associate and became an assistant research professor two years later. He moved quickly through the professorial ranks and became a full professor of physics in 1968. He served as the director of the Frederick Seitz Materials Research Laboratory (MRL) from 1978-1987. He is a fellow of both the American Physical Society and the American Society for Metals.
A distinguished experimentalist, Professor Flynn has made seminal contributions to several areas of condensed matter physics. In the 1960s, he utilized magnetic resonance for a fundamental study of the behavior and motion of defects and impurities in solids, an effort that culminated in his book, Point Defects, an Introduction to the Properties of Imperfect Crystals. It remains the definitive source for this field. Later research focused on the magnetic and electrical responses of defects, and he then expanded his interests to surfaces and films, in addition to bulk specimens.
Professor Flynn pioneered the molecular beam epitaxy (MBE) method of growing metallic superlattices and is largely responsible for the creation of the Epi-Center MBE facility in the MRL. In the last two years, he has been heavily involved with the acquisition, installation, and phased initialization of a low-energy electron microscope (LEEM), one of only five LEEMs currently operational in the United States. To see the first LEEM images taken at Illinois, click here.
An extensive program on the structure and properties of magnetic/non-magnetic superlattices has evolved from his work. Most recently, Professor Flynn, together with Professor Myron B. Salamon, has explored the structure and magnetic behavior of rare earth metals grown as single-crystal thin films by MBE.
Research Area: experimental condensed matter physics, epitaxy, defects and diffusion, magnetism
Description of Current Research
Coherent Properties of Single-Crystal Metallic Superlattices
Metallic superlattices with a high degree of crystalline perfection are produced by molecular beam epitaxy. A rich variety of new properties has been found in Dy/Lu superlattices, which are distinctly different from those of the Dy/Y and Er/Y systems. Recent work has also addressed the behavior of single magnetic layers grown epitaxially and of Nd/Y superlattices. A key element is the effect of strains induced by epitaxy on the magnetic phase diagram. It has proven possible to detect the induced polarization of nonmagnetic constituents of rare-earth alloys using resonant x-ray scattering. Magnetic susceptibility, neutron scattering, and x-ray diffraction methods are used.
Growth and Properties of Single-Crystal Films
The growth processes of single-crystal films prepared by MBE are investigated with a view to applications in rare earth magnetism, surface science, atomic mobility in materials, and the evolution of materials in radiation fields. A specific synthesis route starting with commercial sapphire buffered by bcc refractory metals is being explored. This research uses a low-energy electron microscope (LEEM). It permits exploration of surface morphology and reconstruction during actual growth and under conditions of ultrahigh vacuum at temperatures up to 1400°C. Through diffraction and imaging, the evolution of surface morphology including reconstructions, surface steps, slip bands, threading dislocations, and bulk morphology including screw, edge, and interfacial dislocations and subboundaries can be examined in real time and during actual growth.
Growth and Characterization of Epitaxial GaN
Using Energetic Ion Beams GaN is important for blue light-emitting devices. This research focuses on understanding the initial stages of GaN growth and the enhancement of growth with energetic nitrogen beam deposition. In situ experiments with TEM and LEEM are part of this program.
Selected Publications
Ondrejcek, M, Rajappan, M, Swiech, W, and Flynn, CP. Step fluctuation spectroscopy of Au (111) by LEEM. Surf. Sci. 574, 111-122 (2005).
Ondrejcek, M, Swiech, W, Rajappan, M, and Flynn, CP. Fluctuation spectroscopy of step edges on Pt(111) and Pd(111). Phys. Rev. B 72, 085422-1-12 (2005).
Flynn, CP. Point defect reactions at surfaces and in bulk metals. Phys. Rev. B 71, 085422-1-16 (2005).
Ondrejcek, M, Rajappan, M, Swiech, W, and Flynn, CP. Low energy electron microscopy investigations of kinetics and energetics on clean close-packed metal surfaces. J. Phys.: Cond. Matt. 17, S1397-1406 (2005).
Ondrejcek, M, M Rajappan, W Swiech, and CP Flynn. Low energy electron microscopy investigations of kinetics and energetics on clean close-packed metal surfaces. Proc. of the 4th Intl. LEEM/PEEM Workshop. Twente, Netherlands, May 10-13, 2004. J. Phys.: Cond. Matt. 17, S1397-1406 (2005).
Ondrejcek, M, W Swiech, and CP Flynn. Studies of step stiffnesses and relaxation on Pt(111), Pd(111) and Mo(011). Proc. of the 22nd European Conf. on Surface Science. Prague, Czech Republic, Sept. 7-12, 2003. Surf. Sci. 566, 160-164 (2004).
honors and awards
- Fellow, American Physical Society
- Fellow, American Society for Metals
- NSF International Programs Fellow (1977-78)
- Fellowship of Christ's College, Cambridge (1966-67)
