Higher order photonic stop-bands and random lasing in microflower decorated polystyrene opals

Abstract

Mono-sized polystyrene nanoparticles of different diameters were synthesized using emulsion polymerization process. Consequently, highly ordered 3-D photonic crystals (opals) of polystyrene nanoparticles were fabricated by evaporation assisted sedimentation deposition technique. The opal structures were found to exhibit very intense higher order photonic stop-bands (PSBs) along with the fundamental PSB. Numerically computed band diagram of polystyrene opal endorses the higher order energy bands in the experimental reflection spectra and the existence of Van Hove singularity. Also, on coating the opal structure with a 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) doped polyvinyl alcohol (PVA) thin film (DCM-PVA) active layer, random lasing (RL) was observed. © Anita Publications. All rights reserved.