Departmental Papers (ESE)


In this paper, we investigate theoretically the excitation of modes by a line source, as well as their modal structure and dispersion, in a parallel-plate waveguide that is filled with a pair of parallel slabs; one being a lossless "double-negative (DNG)" material and the other being a lossless conventional "double-positive (DPS)" medium. Previously, we have shown that such "conjugate" pairing of DNG and DPS materials may lead to reduction of size in one-dimensional cavity resonators and waveguides. The analysis presented here describes the proper modes in such a 1-D parallel plate waveguide, and reveals the possibility of no cut-off thickness for this class of parallel-plate waveguides, which implies that a proper TE or TM mode may always be excited in such a waveguide independent of the overall thickness of the waveguide. The excitation of guided modes by a line source and their power-flow peculiarities are discussed, and the analogy to the concept of "open 1-D cavity" in such a waveguide is mentioned. Some of the interesting features and physical insights regarding the power flow in these guided modes will be presented.

Document Type

Conference Paper

Date of this Version

June 2003


Copyright 2003 IEEE. Reprinted from IEEE Antennas and Propagation Society International Symposium, Volume 3, pages 359-362.
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Date Posted: 05 November 2004

This document has been peer reviewed.