NOVEL PHOTOREFRACTIVE SOL-GEL MATERIALS

We have developed new photorefractive media based on hybrid organic-in organic materials containing a charge transporting (CT) molecule eithe r as side-chain or main-chain substituents on the silica backbone. Sec ond order nonlinear optical (NLO) chromophores were introduced either as side chain or as guest units, These materials were prepared by the sol-gel process in the form of thin films of a few mu m-thick. NLO and photorefractive properties have been evaluated using electro-optic me asurements, two beam coupling experiments and photoconductivity measur ements. (C) 1998 Elsevier Science B.V.