Optically induced dichroism and birefringence of disperse red 1 in hybrid polymers

We report results of dichroism and birefringence measurements on Disperse Red 1 (DR1) in hybrid polymers. To investigate the influence of the matrix-chromophore interaction, we employ doped and functionalized systems using three kinds of matrices with different rigidity. Writing, erasing, and rewriting processes are performed on the polymer films at temperatures ranging from 50 to 300 K. Two processes are recognized, the photochemical cis-trans isomerization of the dye molecules and a thermal motion of the photoactive chromophore inside the surrounding matrix. By comparing results obtained from the different network systems, we find that the main parameter correlated with the extent of induced anisotropy is the degree of mobility of the chromophore within the surrounding matrix.