Departmental Papers (ESE)


Here we present the results of our theoretical analysis for guided modes in parallel-plate waveguides filled with pairs of parallel layers made of any two of the following materials: 1) a material with negative real permittivity, but positive real permeability (epsilon-negative); 2) a material with negative real permeability, but positive real permittivity (mu-negative); 3) a material with both negative real permittivity and permeability (double-negative); and 4) a conventional material with both positive real permittivity and permeability (double-positive) in a given range of frequency. Salient properties of these guided modes are studied in terms of how these materials and their parameters are chosen to be paired, and are then compared and contrasted with those of the guided modes in conventional waveguides. Special features such as monomodality in thick waveguides and presence of TE modes with no-cutoff thickness in thin parallel-plate waveguides are highlighted and discussed. Physical insights and intuitive justifications for the mathematical findings are also presented.

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Journal Article

Date of this Version



NOTE: At the time of publication, author Andrea Alù was affiliated with the University Roma Tre. As of September 2006, she is a staff member in the Electrical and Systems Engineering Department at the University of Pennsylvania. Copyright © 2004 IEEE. Reprinted from IEEE Transactions on Microwave Theory and Technniques, Vol. 52, No. 1, January 2004 Publisher URL:

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Double-negative (DNG) material, left-handed (LH) material, metamaterial, negative index material, negative index of refraction, negative permeability, negative permittivity, waveguide



Date Posted: 14 October 2004

This document has been peer reviewed.