Fine tuning photorefractive properties of moleculare photorefractive materials

摘要

To manifest the photorefractive (PR) effect, materials must have the following four functions, charge generating, transporting, trapping, and electro-optic response. Based on this principle, organic PR materials were developed and extensively investigated in the last decade. The general strategy has been to prepare materials that contain moieties playing these four functional roles. A very popular system is the polymer composities playing these four functional roles. A very popular system is the polymer composites containing photoconductive polymers, photosensitizers and nonlinear optical chromophores, which successfully demonstrted impressive PR properties. Multifunctional polymers including all the functional groups into a single polymer chain via covalent bonding have also been developed to overcome the phase separation associated with the polymer composites. More recently, our group found that certain nonlinear optical dye molecules could form homogeneous films and exhibit a large PR effect under an external electric field.