Experimental demonstration of electromagnetic tunneling through an epsilon-near-zero metamaterial at microwave frequencies

TitleExperimental demonstration of electromagnetic tunneling through an epsilon-near-zero metamaterial at microwave frequencies
Publication TypeJournal Article
Year of Publication2008
AuthorsR..P. Liu, Q.. Cheng, T..H. Hand, J.J. Mock, T..J. Cui, S..A. Cummer, D.R. Smith
JournalPhysical Review Letters
Volume100
Issue2
ISBN Number0031-9007
Accession NumberWOS:000252471200032
Abstract

Silveirinha and Engheta have recently proposed that electromagnetic waves can tunnel through a material with an electric permittivity (epsilon) near zero (ENZ). An ENZ material of arbitrary geometry can thus serve as a perfect coupler between incoming and outgoing waveguides with identical cross-sectional area, so long as one dimension of the ENZ is electrically small. In this Letter we present an experimental demonstration of microwave tunneling between two planar waveguides separated by a thin ENZ channel. The ENZ channel consists of a planar waveguide in which complementary split ring resonators are patterned on the lower surface. A tunneling passband is found in transmission measurements, while a two-dimensional spatial map of the electric field distribution reveals a uniform phase variation across the channel-both measurements in agreement with theory and numerical simulations.