Negative Refraction in a Cut-Off Parallel-Plate Waveguide Loaded with Two-Dimensional Lattice of Dielectric Resonators

A two-dimensional (2D) negative-refractive-index metamaterial is proposed, which is composed of a parallel-plate waveguide and a square lattice of dielectric resonators (DR) inserted in it. The collective and macroscopic behavior of the DR lattice under TE resonance gives negative effective permeability whereas the parallel-plate waveguide below the cut-off for fundamental TE modes shows negative effective permittivity, which leads to the left-handedness. The 2D triangular prism of the proposed left-handed waveguide that is sandwiched by right-handed parallel-plate waveguides provides the numerical and experimental demonstrations of the negative refraction for the propagated waves