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Abstract SLJ~:nAF:Y Surface electromagnetic waves are electromagnetic r:.odes that propagate along the interface between two :nedia a:12< wi,•: sE: propat;ation constants depend on the dielectric and ma~netic properties of the two media. In this study, we have discussed (i) the nature of the modes which exist at a single-interface between two ’’edia, (ii) the nature of the modes which exist at thEe two interfaces between three media, (iii) the attenuated total rLflection (ATR) method for coupling volume electron:agnetic waves and surface electromagnetic waves by prisms. ~e have carried out experimental studies of surface electromagnetic waves on clean Ag filrc:s. T~1e ATR technique v.as employed to study the resonant excitation of surface electromagnetic waves on the Ag films by transverse ::;agneti c ( T:.:) polarizeo beams fron: He-Ne C\’ . laser ar;c Argon-Ion C’’ laser using different wavelengths ranging Irom 45?9 A• to 6328 A• The thicknesses of the Ag filn:c1 varied between 200 A• to 1000 A• The ATR spectrum, when the T~ light couples reso!Iantly with surface electromagnetic waves, stwws a minimum at an angle ( 8ATR ) Frorr the angle eATR and the half width c r the minimum ( ~ eATR ) , the real and the imaginary :arts of the dielectric constant of the Ag films were uc~cr~in~o for each film thickness. Th~ vaJ ues ottc.inec . r the complex dielectric constant converge to a limiting value close to the published bulk value. Furthermore, !rum the ATH spectrum, we were able to plot the oispersion relation for the surface electromagnetic waves in the three Jayer configuration (prism/metal/air) for three different tr:icknesses of the Ag film. The three media dispersion relation shows a tendency to approach the dispersion relation, for the surface electromagnetic waves aloni the ir:tcrface of two semi-infinite mecii& (metaJ/air) i.e. unuerturbed two media case. A discussion of the employment of surface electror:, agnetic waves as spectroscopic tool for investigatinG P:ctal surfaces as well as add-layers on metal surfacee .~ j Ke oxioes, are also included. |