Electronic and magnetic materials are enormously valuable in a number of technologies. Professor Chris Leighton (Chemical Engineering and Materials Science) and his research group and collaborators are at the forefront of research into these materials. They are especially interested in research that furthers fundamental knowledge about these materials, but which also may have implications for important industrial applications, such as in information storage and microelectronics. Professor Leighton and his research group use scientific software available through MSI to analyze large datasets containing magnetization, electrical transport, and X-ray diffraction information for magnetic materials. They also generate data by using neutron scattering facilities, which allows study of crystalline structure and magnetic properties.
One class of materials currently under study by the Leighton group is perovskite oxides, materials that have interesting features that correlate with important properties like high-temperature superconductivity and colossal magnetoresistance, which are of great interest to researchers and have practical applications in industry. In a recent paper appearing in Physical Review B, the Leighton group, collaborating with Oak Ridge National Laboratory, published new results on a set of oxides known as perovskite cobaltites. Specifically, they reported comparisons of the properties of the Pr-based cobalt perovskite Pr1-xCaxCoO3-delta (PCCO) with Nd1-xCaxCoO3-delta (NCCO). PCCO has been studied quite heavily recently, and researchers believe that its unique physical properties, in particular a massive change in electrical resistance at a specific temperature, relate to an unusual situation with the material’s Pr-O bond. The authors compared PCCO’s properties to those of NCCO and determined the latter’s phase diagram. This research not only expanded knowledge about the basic physics of narrow bandwidth perovskite cobaltites, but added critical confirmation to the importance of the Pr-O bond in PCCO. It is hoped that future work can build on this to understand the origin of the unusual, and potentially useful, properties of this material. (D. Phelan, Y. Suzuki, S. Wang, A. Huq, C. Leighton. 2013. Structural, transport, and magnetic properties of narrow bandwidth Nd1-xCaxCoO3-delta and comparisons to Pr1-xCaxCoO3-delta. Physical Review B 88 (7) (AUG 9): 075119.)
Professor Leighton was recently named a McKnight Distinguished University Professor by the University of Minnesota.
Image description: Magnetic and electronic phase diagram of NCCO. Temperature axis is on a logarithmic scale. D Phelan, et al., Phys Rev B, 88, 075119 (2013) ©American Physical Society.
posted on May 21, 2014