Absolute luminescence efficiency and photonic band-gap effect of conjugated polymers with top-deposited distributed Bragg reflectors

We study the effects of the deposition of a photonic crystal (PhC) structure, namely a distributed Bragg reflector, on a light-emitting conjugated polymer. The hybrid organic/PhC system is realised by a novel low-temperature reactive electron beam deposition, suitable for the direct fabrication of high-reflective mirrors onto organic soft matter. We investigated the photoluminescence absolute quantum efficiency of the system, finding a yield of 30% after the mirror deposition. We found evidence for the modulation of the output spectra by the photonic band-gap of the coupled PhC, and for the polarisation splitting (as large as 140 meV) of the emitted light.