Optical Salisbury screen with design-tunable resonant absorption bands
Abbreviated Journal Title
J. Appl. Phys.
PERFECT ABSORBER; REGIME; Physics, Applied
A thin-film selective absorber at visible and near infra-red wavelengths is demonstrated. The structure consists of an optically thick layer of gold, a SiO2 dielectric spacer and a partially transparent gold film on top. The optical cavity so formed traps and absorbs light at a resonance wavelength determined by the film thicknesses. Observed fundamental-resonance absorption strengths are in the range 93%-97%. The absorption red-shifts and broadens as the thickness of the top gold layer is decreased with little change in absorption strength. Thus, strong absorption with design-tunable wavelength and width is achieved easily by unstructured blanket depositions. Observed angle-dependent spectra agree well with the recent three-layer analytical model of Shu et al. [Opt. Express 21, 25307 (2013)], if effective medium approximation is used to calculate the permittivity of the top gold film when it becomes discontinuous at the lowest thicknesses. (C) 2014 AIP Publishing LLC.
Journal of Applied Physics
"Optical Salisbury screen with design-tunable resonant absorption bands" (2014). Faculty Bibliography 2010s. 5877.