Light trapping cavity enhanced light transmission through a single sub-wavelength aperture in a metal film.
We demonstrate that optical transmission of a normally incident, monochromatic plane wave through a single sub-wavelength aperture in an opaque metal film can be substantially enhanced by a thin, semitransparent metal film placed parallel to the opaque metal film in front of the aperture. When the semi-transparent and the opaque metal film are separated by a proper distance, a light trapping cavity is formed and the sub-wavelength aperture exhibits a transmission maximum. An enhancement factor of approximately 40 is demonstrated for a cylindrical 100 nm diameter hole in a silver film.
Olkkonen
Juuso
J
VTT Technical Research Centre of Finland, Tietotie 3, P.O. Box 1000, 02044 VTT, Finland. juuso.olkkonen@vtt.fi
D000042:Absorption; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D008567:Membranes, Artificial; D008670:Metals / Q000737:chemistry*; D055096:Optical Devices; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation
D008567:Membranes, Artificial; D008670:Metals