举报
canelsecan
Spatiotemporal instability of ultrashort pulse space-time focusing dispersion effect of self-steepening nonlinear equation based on the spatiotemporal nonlinear dispersive medium instability, expression gain space focusing effect, arbitrary high order dispersion effect and self-steepening effect under the condition of the spectrum modulation instability is obtained. The results show that: in normal and abnormal rate of two populations the dispersion situation, space-time focusing effect will lead to not affect maximum gain instability region of new and original gain spectrum, but to shrink the scope of spectrum, the larger contraction in normal group velocity dispersion, it completely inhibited the growth of high frequency components, in the anomalous group velocity dispersion situation contraction is small. The odd order dispersion effect all right spatiotemporal instability impact, and even order dispersion effect all affect the spatiotemporal instability gain spectrum range without affecting its maximum gain, the effect of the four order dispersion effect and space-time focusing effect on instability similar. Since the main effect effect is steep the modulation gain decreases, which affect regional it lead to the space-time focusing effect of the greater.