Departmental Papers (ESE)


Through experimental investigation, a thin subwavelength cavity resonator was physically realized using a bilayer structure composed of air and a negative permeability metamaterial structure one unit cell in thickness. We designed and built the metamaterial slab with periodic metallic ring structures and measured the spatial electric field magnitude in a cavity formed from this slab and a region of air, showing that a subwavelength cavity can be realized. The measured electric field magnitude distribution in the cavity matched very well with effective medium theory, showing that even a slab one unit cell in thickness may be effectively equivalent to a thin homogeneous medium as far as the construction of a sub-wavelength cavity is concerned, provided that the unit cell size is significantly smaller than the free space wavelength.

Document Type

Journal Article

Date of this Version

June 2007


Copyright 2007 IEEE. Reprinted from IEEE Transactions on Antennas and Propagation, Volume 55, Issue 6, June 2007, pages 1781-1788.

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cavity resonator, metamaterials, microwave cavities, negative index of refraction, negative permeability



Date Posted: 19 August 2007

This document has been peer reviewed.