Revisiting thermal radiation in the near field

Publication date: Available online 28 November 2016 Source:Comptes Rendus Physique Author(s): Jean-Jacques Greffet Thermal radiation is generally assumed to be both spatially and temporally incoherent. In this paper, we challenge this idea. It is possible to design incandescent sources that are directional and spectrally selective by taking advantage of surface waves. We also report the discovery of the enhancement by several orders of magnitude of the energy density close to an interface at a particular frequency as well as the enhancement of the radiative flux between two interfaces when surface phonon polaritons can be excited. These results lead to the design of a novel class of infrared incandescent sources with potential applications in spectroscopy and thermophotovoltaic energy conversion.

Source: Comptes Rendus Physique - November 28, 2016 Category: Physics Source Type: research