INFLUENCE OF THE GLASS-TRANSITION TEMPERATURE AND THE CHROMOPHORE CONTENT ON THE GRATING BUILDUP DYNAMICS OF POLY(N-VINYLCARBAZOLE)-BASED PHOTOREFRACTIVE POLYMERS

The influence of the glass-transition temperature T-g and the electro- optical chromophore content on the grating buildup dynamics in photore fractive polymer composites is investigated The response times were fo und to be strongly dependent on both parameters. In the low-T-g regime , composites of different chromophore content respond similarly quickl y (200-500 ms), whereas significant differences occur for T-g above th e measurement (room) temperature. The composites with the highest chro mophore content give the best steady-state performance; however, their response is much slower than that for those containing less chromopho re. (C) 1998 Optical Society of America.