A New Photorefractive Polymer with Fast Response

Photorefractivity properties of a polymer are investigated by four-wave mixing (FWM) diffraction measurements. The polymer is composed of photoconducting poly (n-vinylcarbazole), photosensitizing 2,4,7-trinitro-9-fluorenone, and optically nonlinear 4-(dicyanoviny1)-N. N-diethylaniline. Its FWM diffraction efficiency and response time as a function of, respectively, electric field and writing intensity have been determined. With a 80μm-think film, a diffraction efficiency of 7.4 x10^-4 has been obtained. The response time of the polymer is as short as 400ms at a writing intensity of 0.17W/cm².