CPM Seminar

New insights into electron and phonon transport in materials:
application to thermoelectrics

Jesse Maassen

Department of Physics and Atmospheric Science
Dalhousie University

My group's research focuses on the science of electro-thermal transport in materials and devices, with the goal of addressing important technological challenges. One such opportunity exists with thermoelectrics, which are materials that can convert heat into electricity. Given that roughly 60% of all energy produced is lost as waste heat, thermoelectrics have the potential to recuperate part of this large, untapped energy source and significantly reduce our global consumption. The challenge is to design or discover advanced thermoelectrics with high conversion efficiency, which requires a fundamental understanding of electron and heat (phonon) transport physics.

In this talk, I will give a brief overview of thermoelectrics and present some of our recent findings from two studies: 1) Investigation of electron transport in layered quasi-2D materials, which we predict possess excellent thermoelectric performance and unusual doping-dependent anisotropic transport. 2) Analysis of phonon transport across a heterojunction, demonstrating the important role of inelastic phonon scattering and non-equilibrium physics that leads to heating/cooling of phonons near the interface. These studies are carried out using predictive modeling based on density functional theory combined with rigorous transport theory. This research is helping to advance thermoelectrics by providing fundamental insights and guiding experimental discovery.