Improvement of holographic recording sensitivities in the green in SiO2 nanoparticle-dispersed methacrylate photopolymers doped with pyrromethene dyes

We demonstrate more than one-order-of-magnitude improvement of holographic recording sensitivities in the green by doping pyrromethene dyes into SiO2 nanoparticle-dispersed methacrylate photopolymer films. Holographic recording dynamics are measured for several dye concentrations and writing intensities. It is found that there exists the optimum writing intensity for a given dye concentration to maximize the diffraction efficiency. Noticeable hologram-apodization phenomena caused by the longitudinal refractive-index changes are also observed in the Bragg-angle selectivity curve.