Photonic band-gap effects upon the light emission from a dye–polymer–opal composite

Abstract

A polymeric photonic crystal formed by impregnating an opal with a Coumarin 6 dye containing polymer has been prepared and its emission properties studied by angular-resolved photoluminescence. A strong spectral redistribution of the luminescence intensity was observed in the dye-polymer-opal compared to that of the dye-polymer reference sample. The emission spectrum shows a marked distortion compared with the reference sample, which changes with the rotation of the crystal due to the angular dispersion of the stop band. Under increasing optical pumping power, a band of amplified spontaneous emission was observed at the stop-band edge. The angular dispersion of the stop band in the luminescence observed from the back surface exhibits in a strong directionality at the maximum of the dye emission band.