DYNAMIC HOLOGRAPHIC IMAGING USING PHOTOREFRACTIVE POLYMERS BASED ON A BORONATE-DERIVATIVE NONLINEAR CHROMOPHORE

Abstract

We report dynamic holographic imaging with organic photorefractive polymer composites, doped with the electro-optic chromophore (2-(p-chlorophenyl)-(3′-nitrobenzo[d])-(4′′-methoxybenzo[h])-1,3-dioxa-6-aza-2-boracyclonon-6-ene, a push-pull molecule derived from a new class of boronates. The composites are based on the photoconductor poly(9-vinylcarbazole) (PVK) as the polymer matrix, and 9-ethylcarbazole (ECZ) as the plasticizer, with the fullerene C 60 as sensitizer. A tilted four-wave mixing geometry was used to record and reconstruct two-dimensional test objects, using a 10 mW He – Ne laser (632.8 nm). The recording response time was less than one second for a light intensity of ≈350 mW/cm 2 in each writing beam. The erasing time had a similar value. These composites have been used for over one year with no appreciable signs of degradation or crystallization.