Dr. Joseph Heremans, Thermal Transport in Weyl Semimetals

Ohio Eminent Scholar and Professor, Mechanical and Aerospace Engineering, The Ohio State University

All dates for this event occur in the past.

264 MacQuigg Labs
105 W. Woodruff Ave.
Columbus, OH 43210
United States

Abstract

The last decade has seen a research focus on the electronic properties of materials with “topological” properties.  The spectrum of the electron excitations in these materials is characterized by topological invariants.  These are properties that do not change under continuous changes of quantities such as interaction strengths, except when some symmetry or related transition occurs. These invariants control the number and nature of the surface and edge states in topological insulators (TI’s) and bulk states in Weyl and Dirac semimetals.

The most convincing evidence for these states comes from angular resolved photoelectron spectroscopy, but real applications must involve electronic transport properties.  Electrical conductivity and Hall effect measurements face experimental difficulties.  In this talk, emphasis will be put on thermal transport properties, namely electronic thermal conductivity, Seebeck and Nernst effects.

Bio

Joseph Heremans is an Ohio Eminent Scholar and Professor in the Mechanical and Aerospace Engineering Department at the Ohio State University, with appointments in the Materials Science and Engineering Department and the Department of Physics.  He is a member of the National Academy of Engineering, and a fellow of AAAS and the American Physical Society.  He joined OSU after a 21 year career in the automotive industry at the General Motors Research Laboratories, where he was the section manager for Semiconductor Physics, and at the Delphi Research Laboratories.  His research interests focus on energy conservation and recovery, and lie at the intersection between experimental condensed matter physics and thermodynamics.  In the last decade, he worked on the transport of heat, charge, and magnetization in solids.