Spectral features of beam propagation in resonant two-level media: II. Propagation of a short-pulse optical beam

The propagation of short light pulses with finite transverse sizes in a res onant medium with a homogeneously broadened transition line is numerically simulated with allowance for diffraction effects. The main attention is foc used on the phase modulation of a pulse due to the transverse self-action o f the beam. It is demonstrated that the shift of the mean frequency of the pulse arising due to phase modulation may be on the order of the transition fine width.