  Based on the recently introduced homogenization theory developed in [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.
