Influence of dispersion on dynamics of the anti-Stokes broadening of the femtosecond pulse spectrum during filamentation in fused silica

Numerical simulation methods are used to study the spectral transformation of a femtosecond wave packet during filamentation in fused silica under conditions of normal, zero, and anomalous group velocity dispersion. It is shown that during plasma generation that causes phase modulation of the light field, a rapid anti-Stokes broadening of the spectrum occurs. It was established that the short-wavelength shift of the broadband supercontinuum spectrum is much larger in case of anomalous group velocity dispersion than in case of normal and zero dispersion. The influence of the wave packet energy on the spectrum broadening dynamics is considered. Estimates of the numerical scheme parameters are obtained based on the dispersion analysis of the process of broadband supercontinuum propagation in a medium.