Microwave-Frequency, Negative-Index Metamaterial Designs Based on Degenerate Dielectric Resonators

In this letter, three different negative-index metamaterial designs based on single-particle degenerate dielectric resonators are presented. The resonator designs are realized by introducing high-contrast perturbations to the cavity geometry so as to bring the lowest-order electric and magnetic cavity resonances into frequency alignment. Since negative-index behavior can be demonstrated with only a single-type resonator (as opposed to dual-particle), these types of degenerate dielectric resonators potentially offer a size advantage so that the structure is less apt to fall outside the effective-medium region.