Characteristics of a waveguide mode in a trilayer Ag/SiO2/Au plasmonic thermal emitter

A suitably designed trilayer Ag/SiO2/Au thermal emitter can be used as the narrow bandwidth infrared light source. The thermal radiation generated in the SiO2 layer resonates between the two metal films and results in not only the Ag/SiO2 surface plasmon polaritons but also the waveguide mode (WM) in the Ag/SiO2/Au structure owing to the thick SiO2 layer. This study investigated the influence of dielectric thickness on energy dispersion relations and derived the theoretical dispersion relation, which fit well with experimental results. This WM light source can be applied in the area of gas sensing and probing the response of the animal cells and plants to infrared radiation. (C) 2009 Optical Society of America