Propagation of Optical Femtosecond Pulses through Quartz and Glass BK-7

In the approximation of dispersion theory to the fourth order inclusive, a theoretical study of the propagation of optical femtosecond pulses of a Gaussian profile and a profile proportional to the hyperbolic secant through quartz and BK-7 glass was carried out. Based on the solutions of the equations for the propagation of pulses of various initial durations through optical materials, dependencies ''material length − pulse duration'' are obtained. It is shown that, compared with the second approximation of dispersion theory, the fourth approximation gives a slightly lengthy pulse duration. Peculiarities of various time pulse profiles on the pulses duration are also shown. Analytical consideration is confirmed by numerical calculations. (author)