PHASE MEASUREMENTS OF SURFACE ELECTROMAGNETIC-WAVES ON SILVER WITH EXCITATION THROUGH THE SUBSTRATE

Surface electromagnetic waves are excited in the visible and near-IR r egions of the spectrum, and interference measurements are performed. T heir excitation is effected by a helium-neon laser (3.39, 1.15, and 0. 63 mu m) on the interface between air and a silver film of thickness 1 00 mu m deposited on a substrate in the form of a prism of fused quart z. The exciting radiation is supplied from the substrate side in a reg ime of total internal reflection in the prism on the edge of the silve r film. The wave vector of the surface electromagnetic wave investigat ed is determined from the results of phase measurements. The dependenc e of the efficiency of the excitation of surface electromagnetic waves on the angle of incidence of the exciting radiation onto the substrat e is investigated. The real part of the dielectric function of the sil ver film is calculated. (C) 1998 American Institute of Physics. [S1063 -7842(98)01003-4].