Dynamic polarization holography. 1. Dynamic polarization-sensitive materials on the basis of azo-dye-containing polymers

The theoretical and experimental investigation of the kinetics of photoanisotropy induction in polarization-sensitive media with significant dark relaxation on the basis of azo dyes in polymer matrices is considered. For improving dynamic characteristics of polarization-sensitive materials, new azo dye N, N-dimethyl-4((4-nitrophenyl)diazenyl)aniline has been specially synthesized, and the kinetics of photoanisotropy induction and relaxation in materials on the basis of this dye has been compared with materials on the basis of Dimethyl Yellow. It is shown that spectral sensitivity of the material with new azo dye is in the range of 470-520 nm, the working range is both in the visible and in the infrared range (from 520 nm at least up to 3400 nm), the maximum meaning of effective anisotropy is 38% (Delta n approximate to 0.022), and the time of photoanisotropy inducing and erasing is approximately 18 ms. It is shown that, if we confine ourselves to meanings of effective anisotropy of approximately 1-2% (Delta n approximate to 0.007), the time of inducing/erasing will be of the order of microseconds. The use of such dynamic polarization-sensitive materials gives the possibility of a new direction-dynamic polarization holography to be developed that combines the possibilities of both dynamic and polarization holography and that opens new prospects for applications. (C) 2009 Optical Society of America