Wavelength-selective and diffuse emitter enhanced by magnetic polaritons for thermophotovoltaics

Both wavelength selectivity and directional insensitivity are highly desired in thermophotovoltaic applications. A concept of a magnetic-polariton-enhanced thermophotovoltaic emitter is presented. The predicted normal emittance from such a nanoengineered surface exceeds 0.8 in the wavelength region from 0.62 to 1.98 mu m and is below 0.2 at wavelengths longer than 2.4 mu m. Furthermore, thermal emission from the proposed structure is diffuse-like as the emittance changes little with the direction up to 75 degrees from the normal. The strip width allows tuning of the emittance spectrum to match particular photovoltaic cells to potentially enhance power generation with improved conversion efficiency. (C) 2012 American Institute of Physics. [doi:10.1063/1.3684874]