Mietheory,1908Exactsolutionof sphere,sphericalsymmetrystructureAbsorption,scattering,andextinctionZenneck(1907)&Sommerfeld(1909)Demonstrated(theoretically)thatradiofrequencysurfaceEMwaves occur attheboundary oftwomedia when onemedium iseithera"lossy"dielectric,orametal,and theother is aloss-freemedium.They also suggested that it is the"lossy"(imaginary)part of thedielectricfunctionthatisresponsibleforbindingtheEM wavetotheinterface
6 Mie theory , 1908 Exact solution of sphere, spherical symmetry structure Absorption, scattering, and extinction
Fano(1939)Suggested that surface EM waves were responsible for the strikinganomalies in the continuous source diffraction spectra of metallicgratings-'Wood'sAnomalies'According to Fano : Surface EM wave, at metal-air interfaces.areevanescent waves whose wave vectors are greater than those of theincident and diffracted bulk EM waves, and that the gratingaugments the wave vector of the incident EM waves enabling themtocouplewiththe surfaceEMwaves.7
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Fano suggested:1. surface EM waves at lossy-dielectric-air interfaces at radiofrequencies (Zenneck-Sommerfeld waves)2. surface EM waves at metal-air interfaces in the optical region(Fanomodes)3. loss-free dielectric/air interfaces (Brewster anle EM waves)"'represent for media of different electrical properties the samesingular case defined by the same mathematical equation'8
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Ritchie(1957)Demonstratedtheoreticallytheexistenceof Surfaceplasmaexcitations (surfaceplasmons)at ametal surfaceStern(1958)Showed(theoretically)thatsurfaceEM wavesatametallic surfaceinvolved EM radiation coupled to surface plasmons.Derived, for the first time, the dispersion relations for surface EMwavesatmetal surfaces9
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Powell&Swan(1960)Observedtheexcitationof surfaceplasmons atmetal interfacesusingelectrons.0tto(1968)Devised the ATR (prism coupling)methodforthe coupling of bulkEMwaves(optical)tosurfaceEMwaves.Kretschmann(1971)Modified the Otto geometry is now the most widely used devicegeometry.Knoll（(1989)Introduced the technique of Surface Plasmon Microscopy10
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