Ultrafast third-order nonlinear optical properties of an azobenzene-containing ionic liquid crystalline polymer

The ultrafast third-order nonlinear optical properties of an azobenzene-containing ionic liquid crystalline polymer were investigated by optical Kerr effect (OKE) and pump-probe techniques with femtosecond pulses. The third-order nonlinear optical susceptibility of the sample solution was obtained to be 2.1 × 10−14 esu at a concentration of 2 × 10−3 M. The temporal response of the sample solution was decomposed into two components, which could be explained by the relaxation of different singlet excited states. The polymer thin film exhibited strong ultrafast nonlinear optical response of 8.26 × 10−10 esu and show its potential applications for further nonlinear optical devices.