Giovanna Scarel, James Madison University
Seminar
Wednesday, September 18, 2013 · 3:30 - 4:30 PM
Are thermal and radiative heat equivalent?
Giovanna Scarel, James Madison University
Our Research Group is interested in harvesting infrared radiation from the solar spectrum and other infrared sources. We use a device called bi-junction power generator (bj-PG). This device behaves according to the Seebeck effect when activated by heat: the voltage produced depends linearly on the temperature difference between the two ends of the bj-PG. This behavior is thermoelectric (TEC) power generation. Surprisingly, the linear relationship is lost when infrared radiation activates the bj-PG. This behavior is infrared (IR) power generation. The experimentally-observed difference motivates the question whether thermal energy and radiative energy are equivalent. This talk will illustrate the journey of our Research Group in answering this question. Thermoelectric and IR power generation, and their difference will be described. Some possible hypotheses on the origin of the difference will be proposed: the interaction of heat and radiation with charged carriers, or the onset of chaotic phenomena affecting the oscillation of quasiparticles (polaritons and plasmons) in the bj-PG. Finally, methods to tune the voltage produced by the bj-PG will be briefly discussed. Among them is the use of atomic layer deposited (ALD) oxide films on various types of substrates.
Giovanna Scarel, James Madison University
Our Research Group is interested in harvesting infrared radiation from the solar spectrum and other infrared sources. We use a device called bi-junction power generator (bj-PG). This device behaves according to the Seebeck effect when activated by heat: the voltage produced depends linearly on the temperature difference between the two ends of the bj-PG. This behavior is thermoelectric (TEC) power generation. Surprisingly, the linear relationship is lost when infrared radiation activates the bj-PG. This behavior is infrared (IR) power generation. The experimentally-observed difference motivates the question whether thermal energy and radiative energy are equivalent. This talk will illustrate the journey of our Research Group in answering this question. Thermoelectric and IR power generation, and their difference will be described. Some possible hypotheses on the origin of the difference will be proposed: the interaction of heat and radiation with charged carriers, or the onset of chaotic phenomena affecting the oscillation of quasiparticles (polaritons and plasmons) in the bj-PG. Finally, methods to tune the voltage produced by the bj-PG will be briefly discussed. Among them is the use of atomic layer deposited (ALD) oxide films on various types of substrates.