Mid-IR characterization of photonic bands in 2D photonic crystals on silicon

We report the characterization of two-dimensional silicon photonic crystals using angular-dependent reflectivity in the mid-IR. The photonic crystals are obtained by electrochemical etching of an ordered array of holes into silicon. The measurements are compared with the theoretical calculations of the corresponding model based on the interaction of the incident light with the photonic crystal sample. A good agreement between the measurements and the calculations is achieved.