Nichtlineare Photonische Kristalle

This project aims at the design, fabrication and characterization of a modular assembly system of non-linear photonic crystals (PhCs) compatible with silicon technology. They will be based on
extended monodomains of aligned macropores mainly in silicon (Si) matrices, but also in titania
(TiO2) for applications in the visible range. The pores will be infiltrated with a consciously designed set of organic and polymeric materials with chromophores based on the phenylene ethynylene motif, exhibiting non-linear optical (NLO) behavior. Additionally, the optical properties of these materials will be probed on the molecular level and bulk polymer level. We will theoretically evaluate various designs for non-linear PhCs. Particular attention will be paid to the controlled generation of specific supramolecular architectures of the molded material. The systematic variation of the degree of polymerization of these rod-shaped molecules and the investigation of corresponding mixtures with optically inactive carrier polymers aims at the tailoring of the concentration, dispersion and orientational distribution of the chromophores. We plan to study the mechanisms of infiltration and mesophase formation aiming at the realization of specific chromophore orientations on a macroscopic scale. PhCs with specific NLO defect structures, such as waveguides, will be prepared by selectively filling individual pores with NLO materials. These wave-guiding structures will allow opto-optical switching and selective emission.