中文摘要：

Dynamic nonlinearities of C 70 /toluene solution are measured and analysed by an improved picosecond time-resolved pump-probe system based on a nonlinear imaging technique with phase object.The photophysical parameters are determined by the five-level model,which is adopted to interpret the experimental data.The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C 70 in picosecond time regime.

英文摘要：

Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters are determined by the five-level model, which is adopted to interpret the experimental data. The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C70 in picosecond time regime.