Selective emitters using photonic crystals for thermophotovoltaic energy conversion

Photonic crystals use a periodic modulation of the refractive index to alter the photonic density of states. The photonic density of states is an important parameter in many phenomena involving radiation-matter interactions - including thermal emission of radiation. Hence, a photonic crystal can be used to engineer the emissivity of an emitter for thermophotovoltaic generators to match the spectral response of the TPV cell. The use of photonic crystals in TPV is described. A three-dimensional photonic crystal in tungsten is realized that exhibits an exceptionally large photonic bandgap and attenuation factor. The photonic crystal is shown to have promise for radiant energy conversion applications like TPV energy conversion.