Local field distribution in random metal–dielectric films; theory and experiment
نویسندگان
چکیده
The local field properties of metal–dielectric films are investigated in terms of the probability distribution function (PDF). For metal coverage p; close to the percolation threshold we obtain a wide, lognormal PDF which for low metal concentrations gradually transforms into a scaling, power-law distribution function. Strong enhancement of the local fields in a broad spectral range is verified by an exact numerical procedure. In experimental studies, metal–dielectric films were synthesized by a pulsed laser deposition technique, and their optical properties were investigated using nearfield optical microscopy. The experimentally and numerically obtained probability functions are found to be in good agreement. r 2003 Elsevier B.V. All rights reserved.
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