Abstract:

Jian Shen

Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831

& Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN 37966

For condensed matter physicists, materials are often separated into two classes:  simple materials and strongly correlated materials. Because the interested problems are very different, there is, traditionally, very little overlap between the two fields. However, in the world of reduced dimensionality, the line is no longer well defined. Simple materials can become complex, and complex materials can become even more complex, or, sometimes, simple. In this talk, I will use a simple material Fe and a complex material LaPrCaMnO3 (LPCMO) to demonstrate that how emerging phenomena appear in reduced dimensionality. For Fe, artificial magnets with tunable exchange interaction have been fabricated to allow magnetic phase transitions that are generally not observable in bulk. For LPCMO, striking transport behavior occurs when the materials are spatially confined. It is hoped that these work will lead to a new field where complexity and quantum effect interplay giving rise to fascinating new properties in exiting materials.   

Brief Bio:

Jian Shen is a senior research staff scientist and a project leader at Oak Ridge National laboratory and an adjunct full professor at the University of Tennessee. His research interest is on the investigation of emerging phenomena at surface, in reduced dimensionality, and at nanometer scale. Specific interest includes magnetism and electronic transport of nanostructured materials and complex oxides, and their underlying physical mechanism. So far he has written three review articles for Surface Science, Surface Science Report, and J.Phys: Condensed Matter on low-dimensional magnetism. He has been served as the chair for the magnetism division in AVS, and has organized many magnetism-related symposia for APS, AVS, MRS and other international conferences. He received his Ph.D from Max-Planck Institut f. Mikrostrukturphyisik in 1996, and became a permanent staff member of Oak Ridge National Laboratory in 1998. His past research has received a number awards including US Presidential Early Career Award for Science and Engineering (PECASE), the Otto-Hahn Medal from Max-Plank Society in Germany, the Guangbiao Chair Professorship from Zhejiang University, the oversea outstanding young researcher award from Chinese NSF, and the Wigner fellowship from Oak Ridge National Laboratory.