Efficient Functionalized Photorefractive Polymers with Infrared Sensitivity

Abstract

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 C60 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/μm. We have found evidence for the formation of aggregates and phase separation in the copolymers.