Third-order optical nonlinearities of a processable main chain polymer with symmetrically substituted tris-azo dyes

A new third-order nonlinear optical (NLO) polymeric material for all-optical waveguide devices is designed, which is a main chain polymer with symmetrically donor-substituted NLO units as part of the polymer backbone. On the basis of the molecular design, the polymer has large third-order NLO susceptibility, χ(3), potentially low propagation loss and high processability for channel waveguide fabrication. The magnitude of χ(3)(−3ω;ω,ω,ω) for the polymer film was 1.5×10−10 esu at the three-photon resonant wavelength. This is the largest value for highly processable polymers.