Resonant Reflectance Anomalies: Effect of Shapes of Surface Irregularities

摘要: It was recently shown that hemispherical pits or bumps on an otherwise flat surface of a sample isotropic material may cause marked anomalies in reflectance near resonant frequencies the material, such as reststrahlen bands ionic dielectrics and plasma metals. The occur even when irregularities are much smaller than wavelength reflected radiation, so incoherently scattered radiation is negligible. effect due to localized resonances somewhat displaced frequency from bulk optic modes by electric boundary conditions. sharp right angle at rim pit bump might have been suspected giving exceptional results. In this paper, problem solved different way demonstrate with well-rounded edges produce approximately same magnitude characteristics bumps. derived classically. Spatial dispersion dielectric nonlinearity assumed be effects very slight roughness curves lithium fluoride aluminum described illustrations.