Globular metal films composed of particles with sizes of the order of the wavelength of visible light can have interesting solar-selective properties when deposited on a metallic surface which provides the required high infrared reflectance. The geometrical nature of the absorption mechanism in these films makes their operation substantially independent of the materials used, and allows wide control of the cut-on wavelength. It is shown here that all-metal films can have poor broadband selective properties; however, the addition of very thin dielectric layers between the globules and the substrate permits surface-wave resonances, giving broadband absorption and a higher solar selectivity. The behavior of these films is found to agree, in various regions, with models based on interference layers, an equivalent circuit, and surface-wave propagation.
© 1978 Optical Society of America
Chris M. Horwitz, "Solar-selective globular metal films," J. Opt. Soc. Am. 68, 1032-1038 (1978)