AgBr nanocrystal-dispersed silsesquioxane–titania hybrid films for holographic materials

AgBr-doped silsesquioxane–titania films with a thickness of approximately 5 μm were prepared using a sol–gel technique. The dopant AgBr crystals were converted into very small Ag nanoparticles (mainly several nanometers) upon blue laser irradiation, leading to an increase in the absorption of the film in the visible region. An excess of Ag + ions in the film was required for the conversion of AgBr into Ag upon blue laser irradiation. A maximum diffraction efficiency of 0.03% was achieved after two-beam interference exposure with a blue laser for 1300 s. These results imply that the films are suitable for use as holographic materials.