Journal of Applied Polymer Science, Vol.120, No.5, 3065-3070, 2011
Nonlinear Optical Response of Liquid Crystalline Azo-Dendrimer in Picosecond and CW Regimes
The nonlinear optical response of the liquid crystalline multiarm star-shaped azodendrimer was investigated in picosecond pulse and CW regimes at 532 nm. The polymer exhibited large nonlinear refractive coefficient in two regimes (n(2) = -2.88 x 10(-13) cm(2) /W and -1.1 x 10(-10) cm(2) /W under picoseconds pulse excitation, whereas n(2) = -1.4 x 10(-6) cm(2) /W and n(2) = -8.8 x 10(-5) cm(2)/W under CW laser excitation in solution and film, respectively). The mechanism accounting for the process of nonlinear refraction was discussed. The value of photoinduced birefringence in the polymer film was also measured (Delta n similar to 10(-3)) under CW laser excitation at 532 nm. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 120: 3065-3070, 2011