Design of a high-performance photorefractive (PR) polymer composite relies on combining various components to perform certain functionality in the composite. Below are some of these components, their functions, and an example of such a compound.

Sensitizer (S) - A sensitizer is typically added at concentrations of 0.1-1 wt% to promote charge carrier photogeneration. The choice of the sensitizer is determined by the wavelength of photorefractive grating recording. (Examples: C60 and TNF)

Photoconductive Polymer - Provides transport sites for efficient charge (typically hole) transport. (Examples: PVK and PPV derivatives)

Nonlinear Optical Chromophore (NLO) - Needed for an electric field dependent refractive index via birefringence (due to reorientation of polar molecules in the electric field) and electro-optic effect. Typical concentrations of NLO chromophores in the composite are 25-35 wt%. (Examples: MNPAA and AODCST)

Plasticizer (PL) - Needed to lower the glass transition temperature (Tg) of the composite and promote chromophore orientation in the electric field in order to take advantage of the orientational enhancement effect. (Examples: BBP and ECZ)

Some molecules can serve as photoconductors and NLO chromophores at the same time, as well as exhibit glass-forming properties with Tg around room temperature. The only dopant which is needed in this case is a sensitizer. Such organic amorphous glasses are among best-performing organic PR materials. (Examples: DCDHF-6 and ATOP-4)

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