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
11 Mie theory , 1908 Exact solution of sphere, spherical symmetry structure Absorption, scattering, and extinction
TheoryRitchie(1957)Demonstratedtheoreticallytheexistenceof Surfaceplasmaexcitations (surfaceplasmons)at a metal surfaceStern(1958)Showed(theoretically)thatsurfaceEM wavesatametallic surfaceinvolvedEMradiation coupledto surfaceplasmonsDerived, for the first time, the dispersion relations for surface EMwavesatmetal surfaces12
12 Theory
ExperimentPowell&Swan(1960)Observed the excitation of surfaceplasmons at metal interfacesusing electrons.0tto(1968)Devised the ATR (prism coupling) method for the coupling of bulkEM waves (optical)tosurfaceEM waves.Kretschmann(1971)Modified the Otto geometry is now the most widely used devicegeometry.Knoll(1989)Introduced the technique of Surface Plasmon Microscopy13
13 Experiment
Extraordinary optical transmissionT.W.Ebbesengroup,1998StartpointofSPPBottleneck:low lighttransmittivityofapertures smallerthanthe wavelengthofincident photonHolearraysinsilverfilm:metalfilmthickness1Periodicity of holessao:dScale of holesResults:ExtraordinarytransmissionMaximum at X/d~10Influenceoft(inAPL)Explanation:Couplingof lightandplasmons0.51.522.5Wavelength/period14ExtraordinaryopticaltransmissionthroughsubwavelengthholesT.W.Ebbesenetal,NATURE/VOL39112FEBRUARY1998
14 Bottleneck: low light transmittivity of apertures smaller than the wavelength of incident photon Hole arrays in silver film: metal film thickness t Periodicity of holes a0 Scale of holes d Results: Extraordinary transmission Maximum at λ/d~10 Influence of t (in APL) Explanation: Coupling of light and plasmons Extraordinary optical transmission T.W.Ebbesen group , 1998 Extraordinary optical transmission through subwavelength holes T.W. Ebbesen et al, NATURE |VOL 391 | 12 FEBRUARY 1998 Start point of SPP
Beaminglightfromabull'seyesstructureT.W.Ebbesengroup,2002ProgressworkBTosolve:lightdiffractsinalldirectionswhenanapertureissmall.0.6Bull's eye of Ag film:0.2thickness300nmGrooveperiodicityy500nm400500600700800900Wavelength (nm)DCAnddepth60nmHolediamter250nm0.Results:Beaming lightAnoiedenExplanation:Couplingoflightandplasmons15Beaming lightfromasubwavelengthhole,T.W.Ebbesenetal,Science,297,820(2002)
15 Beaming light from a bull’s eyes structure T.W.Ebbesen group , 2002 Progress work Beaming light from a subwavelength hole, T.W. Ebbesen et al, Science,297,820(2002) To solve: light diffracts in all directions when an aperture is small. Bull’s eye of Ag film: thickness 300nm Groove periodicity 500nm And depth 60nm Hole diamter 250nm Results: Beaming light Explanation: Coupling of light and plasmons