10:00 AM - 11:00 AM
Olivier Delaire, Scattering and Thermophysics Group, MSTD, ORNL, Oak Ridge Materials and Chemistry Seminar Series
Email: Adrian SabauPhone:
A microscopic understanding of heat transport is of broad interest for the design of efficient energy materials, and relies on a detailed knowledge of phonon dispersions and mean-free-paths to establish reliable atomistic models of thermal conductivity. Inelastic neutron scattering (INS) instruments at SNS and HFIR can map excitations throughout reciprocal space efficiently, and measurements on single-crystals provide quantitative accounts of phonon scattering mechanisms, including anharmonicity, electron-phonon coupling, and scattering by defects or nanostructures. Such microscopic information about phonon mean-free-paths provides important insights to design more efficient thermoelectric materials, for example. The neutron scattering studies are strongly complemented with ORNL’s capabilities in crystal growth and first-principles modeling. I will present results from our recent investigations of thermal transport in several important thermoelectric materials. In addition, phonons often provide a large contribution to the entropy of a material, and I will discuss several cases where INS contributed to a detailed understanding of the thermodynamics.
Coffee and cookies will be available first come first serve from 9:30-10:00AM.