Reversible change of diffraction efficiency in Cl-containing 3-glycidoxypropyl silsesquioxane films co-doped with Ag and Cu

摘要

The reversible change of diffraction efficiency is confirmed in the sol–gel-derived Cl-containing inorganic–organic hybrid films co-doped with Ag and Cu by interfered blue and green laser irradiations. The change of diffraction efficiency is due to absorbance change, which is caused by a mutual conversion of Ag and AgCl nanoparticles upon the laser irradiations. The role of Cu is clarified that electrons are transferred between Ag and Cu, which is indispensable for the reversibility of the absorbance change. The Ag nanoparticles are observed to be aggregated after several cycles of blue and green laser irradiations. The aggregation would occur because of the migration of Ag element during laser irradiation. The diffraction efficiency of the film reaches 0.75% after interfered blue laser irradiation; then it decreases almost 0% by green laser irradiation. Subsequent interfered blue laser irradiation increases again the diffraction efficiency up to 0.59%. This suggests that our materials can be used as rewritable hologram recording media.