Dynamics of photorefractive grating erasure in polymeric composites

Theoretical and experimental studies are presented of the dynamics of photo refractive grating erasure in polymeric photorefractive materials with hole traps. A bi-exponential decay for the rate of optical erasing of the space -charge field has been obtained by theoretical solution. The optically indu ced erasure rate for polymeric photorefractive materials is theoretically p redicted to depend on optical intensity as a sublinear relation of I-alpha, in which alpha is dependent on the electric field. The characteristics of the traps in a photorefractive material play a key role in the dynamics of grating erasure. Experimentally studied was the dynamic process of erasing the photorefractive grating in a polymeric composite, poly-N-vinylcarbazole : fullerene: diethyl aminonitrostyrene:tricresyl phosphate. The theoretical analysis and experimental results reveal that shallow traps are dominant i n this photorefractive material. (C) 1999 American Institute of Physics. [S 0021-8979(99)02701-2].