Generalized retrieval method for metamaterial constitutive parameters based on a physically driven homogenization approach

Abstract

Based on the recently introduced homogenization theory developed by Al\`u [Phys. Rev. B 84, 075153 (2011)], we propose a generalized retrieval method that allows extracting physically meaningful bulk effective parameters from conventional scattering measurements of periodic metamaterial samples composed of subwavelength inclusions. We show that, compared to conventional approaches, our method is able to capture the anomalous physics in the wave interaction with resonant metamaterials and return physically meaningful homogenized parameters that retain local properties in the long-wavelength limit. As a byproduct, we are also able to retrieve the polarizabilities of the constituent inclusions, which are shown to satisfy expected dispersion properties for passive inclusions, in contrast with conventional retrieval approaches.