The impact of group velocity dispersion on femtosecond laser filamentation with higher-order Kerr effect at different atmospheric pressures

Abstract

The impact of group velocity dispersion (GVD) on femtosecond laser filamentation with the higher-order Kerr effect is studied at different atmospheric pressures. The results show that GVD makes the collapse distance to not meet the semi-empirical formula proposed by Dawes and Marburger, suppresses multiple focusing and splitting in time during the propagation process, and reduces the length of filament. In addition, we also compared the results with those considering only the third-order Kerr effect. This provides some information for the study of whether the defocus effect in the femtosecond laser filamentation is the higher-order Kerr effect or the plasma effect.