Photorefractivity and Optical Transmittance of Hybrid Liquid Crystal Cell with Homeotropically Photoaligned Layer and Fullerene Initiation

A hybrid photorefractive liquid crystal cell was prepared with poly(9-vinylcarbazole) as a photoconduction layer and with a photocrosslinkable polymer of the pendant cinnamoyl group as a vertical photoalignment layer. The hybrid structure could increase the diffraction efficiency and transmittance by eliminating light loss by undesirable scattering of the incident beam through the liquid crystal cell. The use of the photoalignment layer in the hybrid liquid crystal structure resulted in a gain coefficient over 900 cm -1 , diffraction efficiency over 13%, and transmittance over 85%. These results indicate that the hybrid cell design provides high efficiency for many applications in real-time holography and data storage devices.