Nonlinear optical properties and photoinduced anisotropy of an azobenzene ionic liquid-crystalline polymer

摘要

The nonlinear optical properties and photoinduced anisotropy of an azobenzene ionic liquid-crystalline polymer were investigated. The single beam Z-scan measurement showed the polymer film possessed a value of nonlinear refractive index n_(2) velence -1.07 X 10~(-9) cm~(2)/W under a picosecond 532 nm excitation. Photoinduced anisotropy in the polymer was studied through dichroism and photoinduced birefringence. A photoinduced birefringence value (DELTA)n approx 10~(-2) was achieved in the polymer film. The mechanism for the nonlinear optical response and the physical process of photoinduced anisotropy in the polymer were discussed.