All-optical limiter photonic crystal with two-photon absorption

We present in this paper an original theory, modeling, and numerical calculations to make an all-optical limiter based on a two-photon absorption (TPA) nonlinear 2D parallel cylinders upon a triangular geometry photonic crystal in the visible domain. The structure could be either broadband or narrowband and is quasi-invariant to the incidence angle. The parameters used for the cylinders were extracted from the literature (combination of TiO2 and nonlinear ZnO cylinders presenting TPA). This device could be useful, for instance, to protect photodetectors from an intense incident laser beam. (c) 2022 Optica Publishing Group