Friday 12 Nov 2021: Engineering and measurement of thermal radiation
Mikhail Kats - University of Wisconsin-Madison
Thermal radiation is the phenomenon responsible for most of the light in the universe. Though understanding of thermal radiation dates back over a century, recent advances have encouraged the re-examination of this phenomenon and its applications. This talk will describe our group’s advances and outline future work in the measurement and manipulation of thermal radiation. First, I will discuss our innovations in thermal-radiation metrology, especially for low-temperature thermal emitters, emitters with temperature-dependent emissivity, and emitters out of equilibrium. Such improvements can enable techniques such as our recently demonstrated technique of depth thermography, in which measurements of thermal radiation yield temperature information below the surface of objects. I will also describe our invention of a minimalistic spectroscopy technique that requires no gratings, interferometers, or any other wavelength-selective components. Then, I will describe the use of phase-transition materials including vanadium dioxide and rare-earth nickelates to demonstrate new phenomena, including negative- and zero-differential thermal emittance. I will also discuss our recent demonstration of nanosecond-scale modulation of emissivity and thermal-radiation pulses down to picosecond scales. The talk will include discussion of exciting opportunities of thermal-radiation engineering for infrared privacy, thermoregulation, vapor condensation, and light-propelled space travel.