Novel Molecules for Photorefractive Application

Abstract

Abstract Monolithic multifunctional chromophores have been developed as a new class of organic photorefractive materials. Oligomeric carbazole molecular systems in the form of starburst dendrimers and conjugated trimers were studied. Molecular solids of acceptor-substituted carbazole oligomers and dendrimers exhibit glass transition. The second-order nonlinear optical coefficients d ij were determined to be 50 pm/V by second-harmonic generation measurements. We also examined the photoconductive properties by the xerographic discharge method. Two beam coupling and four-wave mixing experiments were performed to characterize photorefractivities. The photorefractive phase shift measurement indicated that the induced index grating is shifted by 90[ddot] with respect to the absorption grating. Unlike usual photorefractive polymers containing multi-component systems these multifunctional chromophores can be applied to monolithic photorefractive materials.