WAVEGUIDES FILLED WITH BILAYERS OF DOUBLE-NEGATIVE (DNG) AND DOUBLE-POSITIVE (DPS) METAMATERIALS

Abstract

Simple normalized dispersion relations for transverse magnetic (TM) and transverse electric (TE) propagating modes in parallel-plate waveguides fllled with DPS/DPS or DNG/DNG, and DNG/DPS bilayers are presented. The evanescent TE0 mode of the waveguide fllled with a DNG/DPS bilayer is characterized also by a simple normalized dispersion relation. Since an important behavior of the modes in the waveguide fllled with a DNG/DPS bilayer is the existence of a turning point (TP) at which the power carried by the respective mode on the propagation direction equals zero and changes the sign, we present also implicit relations for determining the normalized parameters of the TM and TE modes at that TP. We show that the TP begins to exist at certain values of the normalized parameter v2 characterizing the DPS layer. For both the TM and TE modes, the higher is the mode order, the greater is the v2 parameter at which the TP begins to exist, but the behavior of the TP is difierent for the TM and TE modes.