Experimental evidence of resonant effective permittivity in a dielectric metamaterial

We designed and fabricated a dielectric metamaterial consisting of one set of high permittivity resonators. We experimentally showed that this metamaterial exhibits resonant effective permittivity, issued from the second mode of Mie resonances of these resonators. Therefore, metamaterials consisting of high permittivity resonators may provide either effective permeability or permittivity issued from the first two modes of Mie resonances, respectively. This ensures that all-dielectric metamaterials involving two sets of matched high permittivity resonators may exhibit negative index issued from these two modes, notably up to the terahertz domain.