Abstract

Since their discovery, photorefractive materials remain in the focus of photonic research¹ Photorefractive behavior has been shown to manifest itself in a wide variety of device-utilizable effects. This feature is anticipated to make photorefractive materials very important to photonic technology. These materials will find practical utility only when they are easier to process, their high electrooptic coefficients are not accompanied by high polarizability, and the tradeoff between the speed and the dynamics of the response is overcome. These are also the main limitations of the well studied photorefractive inorganic crystals! Photorefractivity has been demonstrated recently also in polymeric films.^2,3 These materials offer an unique opportunity of addressing separately the limitations of inorganics mentioned above by the molecular design of a polymeric composite film.^3,4 Diffraction efficiencies close to 2% and two-beam coupling gain of 4 cm^-1 have already been here successfully achieved in our laboratory.^4,5

© 1993 Optical Society of America