Thermoelectric materials are important for spacecraft power, waste heat recovery, thermal management and cooling applications. Here I discuss the basic physics of thermoelectric effects and approaches for discovering new thermoelectric materials. A key issue is the contraindication of high thermoelectric performance, which places thermoelectrics into an interesting group of materials that includes transparent conductors, magnetic semiconductors and multiferroics. The efficiency of thermoelectric systems is limited by materials performance. This is measured by the figure of merit ZT=oS2T/k, where S is the thermopower and the other symbols have their usual meaning. ZT is therefore a composite property involving electronic and thermal transport, with high ZT favored by high conductivity, high thermopower and low thermal conductivity. However, these properties are inter-related, often to the detriment of ZT. These relationships, however, lead to fascinating connections between thermoelectric performance and other forefront topics in condensed matter, including topological insulators, ferroelectrics, photovoltaic materials and others. This talk explores these connections and ways of achieving high ZT.
Event Date and Time
David Singh, University of Missouri