All-optical poling kinetics of azophenylcarbazoles influenced by attached anchor

Second order non-linear optical features of anchor attached azophenylcarbazole based derivative 9-(2,3-epoxy)propyl-2-(2,3-epoxy)propoxy-3-(4-nitrophenyl)azo-9H-carbazole dispersed in polycarbonate was investigated. Using all-optical poling technique writing and reading kinetics of second order susceptibility gratings were measured. Theoretical modelling of the experimental results revealed one cis-trans thermoisomerization rates k₁= 1.44×10^-3 s^-1, which is twice or more times less than for the branched donors, depended on branching. Two arguments have been raised to explain the anchor influenced decrease in cis isomer flexibility. The investigated input of orientational diffusion confirmed the conclusion.