Ultrafast third-order nonlinear optical response of two soluble multi-wall carbon nanotubes

Abstract

Using femtosecond time-resolved optical Kerr technique, the ultrafast third-order nonlinear optical response of two soluble multi-wall carbon nanotubes (MWNTs), MWNToda and MWNTols, was measured at wavelengths of 640 nm and 830 nm, respectively. The experimental results reveal that, the value of the average hyperpolarizability per each carbon atom γav can reach to 2.0 × 10−32 esu. Moreover, obvious aggregation effect on γav was demonstrated.