The blackbody radiation spectrum is fundamental to any thermal emitter. However, by properly designing the emitter structure, a narrow bandwidth and high power infrared source can be achieved. This invention consists of a triple layer structure by sandwiching a dielectric SiO 2 layer between two Ag metal films on the Si substrate. The top Ag layer is perforated by periodic holes. When the device was heated, the background thermal radiation was suppressed by the bottom Ag whose emissivity is very low. The thermal radiation generated in the SiO 2 layer resonant between two metal films and the Ag/ SiO 2 and the Ag/air surface plasmon polaritons are induced and converted to light radiation. Strong resonance at Ag/ SiO 2 ͑1,0͒ degenerate modes results in the coherent light radiation at the wavelength associated with the dielectric constant of SiO 2 and the lattice constant of the perforated hole array. The ratio of the full width at half maximum to the peak wavelength is 0.114. This narrow bandwidth and high power infrared light source can be used to explore the biological response of cells and plants.

In this letter, the effect of extraordinary transmission of periodic metal hole arrays is directly integrated into the quantum dot infrared photodetector with broadband response. It is found that the detector response is strongly modulated by the extraordinary transmission from the excitation of surface plasmon.

The reflection and emission properties of an infrared emitter, which is a plasmonic multilayer structure consisting of a relief metallic grating, a waveguide layer, and a metallic substrate are investigated both experimentally and theoretically. A localized surface plasmon polariton (SPP) mode which is angular-independent in almost the full range of incident angles is observed. The thermal emission of this structure is also measured. It is found that the emission peak coincides with the angular-independent localized SPP mode. In addition, the emission spectrum of the plasmonic emitter can be predicted by investigating the reflectance spectrum.