Double Wavelength Infrared Emission by Localized Surface Plasmonic Thermal Emitter

A double wavelength infrared emission by plasmonic thermal emitter using stacked Au/SiO2/Au/SiO2/Au structure was investigated. The effective refractive index of sandwiched SiO2 is higher than normal value due to the coupling of surface plasmons at the top and bottom Au/SiO2 interfaces. Two different localized surface plasmon modes were excited with the same metal width, but different SiO2 layer thicknesses in top and bottom Au/SiO2/Au tri-layer structures. The measured dispersion relation diagram and simulation demonstrated that the resonances were localized resonance and the distribution of magnetic field was concentrated at the central SiO2 layer between two Au layers.