Formation of a sequence of ultrashort signals in a collision of pulses consisting of a small number of oscillations of the light field in nonlinear optical media

Collisions of pulses consisting of a small number of oscillations and propagating in a nonlinear optical medium unidirectionally but with different group velocities because of a difference in the spectral composition are considered. It is shown that, at intensities of radiation ensuring the superbroadening of its spectrum, the interaction of two pulses can result in the formation of a quasi-discrete spectral supercontinuum whose temporal structure is described by a sequence of ultrashort signals with a nearly rectangular shape.