Holographic storage in photoresponsive crosslinked polymer-liquid crystalscomposites

Holographic gratings were formed by using crosslinked polymer-liquid crysta l composites containing azobenzenes. The holographic recording was based on photoinduced alignment of a nematic liquid crystal filled in a cell as a r esult of the amplification of photoreorientation of azobenzene residues and exhibited volume holographic properties with Bragg diffraction. Spatial fr equency of 1 mum was obtained for a cell of 200 mum in thickness. whereas d iffraction efficiencies depended on holographic exposure doses and cell thi ckness. A free-standing film of this composite system was also prepared to perform holographic recording.