Coherent thermal emission from one-dimensional photonic crystals

Coherent thermal emission from surface relief gratings holds promise for spectral and directional control of thermal radiation but is limited to transverse magnetic waves, which can excite surface plasmon or phonon polaritons in the grating structure. We show in this letter that a coherent thermal source can be constructed with a thin polar material coated on a one-dimensional photonic crystal. The excitation of surface waves at the interface of the coated layer and the photonic crystal results in highly spectral and directional emission in the infrared for both the transverse electric wave and the transverse magnetic wave. (C) 2005 American Institute of Physics.