Physics CM/BIO/ECE Seminar Series Presents: Jifeng Sun

Wednesday, May 2, 2018 4:00pm

Room 223A, Physics Building Library

Departments: 

physics bldg

The MU Physics & Astronomy Department’s Condensed Matter - Biological Physics - Electrical & Computer Engineering seminar series presents, "Understanding the High Performance Thermoelectrics from Electronic Structures," by Jifeng Sun, a postdoctoral fellow in the MU Department of Physics & Astronomy, Wednesday, May 2, 4:00 p.m., Room 223A, Physics Building Library. Refreshments will be served beginning at 3:30 p.m.

Sun writes, "Thermoelectric effect is an attracting technology which enables direct conversion between thermal and electrical energy, thus providing an alternative for power generation and refrigeration. However, thermoelectric performance is a contraindicated property of matter that requires combinations of transport properties that do not occur in ordinary materials. Finding new high performance thermoelectrics requires methods for efficiently screening compounds to detect the unusual electronic structures that can decouple transport quantities, especially for power factor, the Seebeck coefficient and the conductivity. Here we present and test a simple transport function that can be efficiently calculated using standard methods and which identifies materials that decouple these transport quantities. It is large for band structures that overcome the inverse relationship between σ and S regardless of the specific characteristic that does this, i.e. complex band shapes, multiple valleys, heavy-light band mixtures, band convergence, valley anisotropy, and other features. Thus, this transport function provides a simple and easily used way to screen materials for potential TE performance. Several selected promising thermoelectric materials which are screened by the function will be discussed as well."