Departmental Papers (ESE)


Recently, there has been an increased interest in the problem of wave transmission through sub-wavelength apertures, following successful experimental demonstration by several groups for enhancing optical power transmission through nano-scale holes in metallic screens due to properly designed periodic corrugation. Oliner, Jackson, and their co-workers explained and justified this phenomenon as the result of the excitation of the leaky waves supported by the corrugated screen. Here we discuss in detail the mechanism and analysis for another setup we have recently proposed, in which metamaterial layers with special parameters may be utilized as covers over a single sub-wavelength aperture in a perfectly electric conducting (PEC) flat screen in order to increase the wave transmission through this aperture, and we provide a detailed physical insights and analytical explanation for this aperture setup that may lead to similar, potentially even more pronounced effects when the proper metamaterial layers are used in the entrance and the exit face of the hole in the flat PEC screen with no corrugation. Some numerical results confirming this theory are presented and discussed. We also investigate the sensitivity of the transmission enhancement to the geometrical and electromagnetic parameters of this structure.

Document Type

Journal Article

Date of this Version

June 2006


At the time of publication, author Andrea Alù was affiliated with the University of Roma Tre. As of September 2006, she is a staff member in the Department of Electrical and Systems Engineering at the University of Pennsylvania. Copyright 2006 IEEE. Reprinted from IEEE Transactions on Antennas and Propagation, Volume 54, Issue 6, June 2006, pages 1632-1643.

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Aperture coupling, aperture enhancement, leaky wave, metamaterials, polariton, sub-wavelength aperture



Date Posted: 21 June 2006

This document has been peer reviewed.