Modeling of optical properties of reflectionless coatings on the basis of nanocomposite materials

Full text : Investigations on creation of layered systems, which provide practically reflectionless transmission through them electromagnetic radiations, are very important for many applications in optics. Coatings on the basis of nanocomposite materials can be optimized for specific applications by modifying their particle size, shape, volume fraction, microstructure, etc. Composite materials that contain particles much smaller than the wavelength of incident radiation can be modeled by effective medium theories. Optical properties of composite medium consisting of a transparent dielectric matrix with inclusion of metallic nanoparticles are investigated theoretically. At the assumption of small sizes of filler particles (in comparison with the incident radiation wavelength), the effect of volume fraction of metallic particles δ (copper, gold, etc.), layer thickness ι and optical parameters of substances of a coating are investigated on the antireflection conditions. The fundamental quantity describing the dielectric response of nanocomposite material is the effective complex dielectric function ε which can be expressed by the formula. Using complex reflection coefficient expression for multilayer system the selective quantities of coating thickness and volume fraction of metal particles to realize antireflection are calculated