Narrow-band midinfrared thermal emitter based on photonic crystal for NDIR gas sensor

A high performance plasmonic thermal emitter with narrow bandwidth emission property were proposed and fabricated. This emitter is based on a metal coated two-dimensional (2D) photonic crystal of air holes in a silicon substrate. The PC structure is found to be highly effective in suppressing the thermal emission, which can yield 2 orders of magnitude more efficient that conventional IR sources. Thermally isolated, uniformly heated emitters, with photonic crystal structure modified surfaces are exploited for narrow-band spectral tuning in the infrared wavelength regime. The results show that narrow band spectral tuning is accomplished through control of the lattice constant of the PC patterns.