OBSERVATION OF PULSE SPLITTING IN NONLINEAR DISPERSIVE MEDIA

We investigate experimentally the nonlinear dynamics of a femtosecond pulse undergoing self-focusing in a normally dispersive medium. Above a certain threshold power, we observe that the pulse splits into two p ulses, and measurements of the pulse spectra provide evidence that sup ercontinuum generation is closely connected with the temporal splittin g. We also observe that the split pulses can undergo additional splitt ings. Our observations are in good agreement with the predictions of t he theoretical model based on the nonlinear Schrodinger equation descr ibing self-focusing in dispersive media.