Optical nonlinearity and structural phase-transition observation of organic dye-doped polymer-silica hybrid material

The optical nonlinearity of organic dye-doped poly(methyl methacrylate) (PM MA)-silica-gel hybrid material was investigated by second-harmonic-generati on measurement. We found that incorporation of in situ polymerized solgel p recursors into the organic dye-doped PMMA. significantly improved the nonli near optical stability of the system. However, improvement of thermal stabi lity occurred only when a sufficient amount of silica I:el was incorporated . A structural phase transition from pure polymer to a hybrid system was fo und near a 10-mol.% silica-gel concentration. The optimum polymer/tetraetho xysilane molar ratio is 2:1 to 1:1. (C) 1999 Optical Society of America OCI S code: 190.4710.