Optical nonlinearity and photoinduced anisotropy of an azobenzene- containing ionic liquid crystalline polymer

摘要

The nonlinear optical properties of an azobenzene-containing ionic liquid crystalline polymer were investigated using single-beam Z-scan and optical Kerr effect (OKE). The polymer film exhibited large nonlinear absorption (～10-6 cm W-1) and nonlinear refraction (～10 ~(-11) cm~2 W~(-1)) under 532 nm ps excitation. The femtosecond time-resolved OKE results suggested that the nonlinear optical response time in off-resonant region was as fast as 300 fs. Moreover, stable molecular reorientation and a large photoinduced birefringence ($ sim!10^{ - 1} $) were achieved in the polymer film with a 405 nm continous wave (CW) laser as pump light. The large optical nonlinearity, ultrafast response, and effective photoinduced molecular reorientation of the polymer films indicated their potential applications in nonlinear photonic devices and optical storage.