ИСТИНА

Using numerical simulation, we study the effect of anomalous group velocity dispersion (AGVD) on the light bullets (LB) arising in the course of filamentation of mid-IR femtosecond pulses in fused silica. As the parameter determining the influence of AGVD was chosen a ratio of the dispersion length to the diffraction length. It is found that depending on the ratio between characteristic lengths of wave packet the threshold power of filamentation and the distance to the start of the filament can decrease in comparison with critical power of stationary self-focusing