Journal of physical chemistry b vol:106 issue:18 pages:4588-4595
We have prepared new photorefractive methacrylate copolymers functionalized with a highly polar bifunctional chromophore. The photorefractive response was studied by ellipsometry, four-wave mixing, and two-beam coupling and is compared to that of polymers and polymer composites studied previously. The polymer could be sensitized with C-60 for operation at the writing wavelength of 780 nm, which results in an improved grating build-up time. At this wavelength, we have observed overmodulation of the internal diffraction efficiency at an applied bias field of 43 V/mum. We have found evidence for the formation of aggregates and phase separation in the copolymers.