Increase of SRG modulation depth in azopolymers-nanoparticles hybrid materials

Thin films of azopolymer-nanoparticles hybrid materials were fabricated with poly[1-[4-(3-carboxy-4hydroxyphenylazo) benzenesulfonamido]-1,2-ethanediyl] (PAZO) and different concentrations of Ag and AgAu nanoparticles (NPs). By illuminating the films with polarized interference patterns, surface relief gratings (SRGs) were recorded. It was found that for some concentrations of NPs their modulations and diffraction efficiency were higher than the obtained for PAZO films without NPs. The effect was mainly explained by the increase of the free volume available for the photoisomerization for certain concentrations of NPs. The dependence of the diffraction efficiency on concentration was directly related to changes in modulation depth. When doping with NPs, the maximum efficiency increases more than two times the efficiency without NPs.

Automated summary

Thin films of azopolymer-nanoparticles hybrid materials were fabricated with different concentrations of Ag and AgAu nanoparticles, resulting in higher modulations and diffraction efficiency compared to films without nanoparticles. The increase in efficiency was explained by the increase in free volume available for photoisomerization with certain concentrations of nanoparticles. The dependence of diffraction efficiency on concentration was directly related to changes in modulation depth, with maximum efficiency increasing over two times when doped with nanoparticles.