Nonlinear propagation of optical pulses of a few oscillations duration in dielectric media

Using a semi-phenomenological model of the polarization response of an isotropic solid dielectric that does not resort to the slowly-varying-envelope approximation, we have obtained a nonlinear wave equation for the electric field of a femtosecond light pulse propagating in the given dielectric. Evidence is presented that this equation possesses breatherlike solutions in the region of anomalous group dispersion and does not have any solutions in the form of steady-state traveling solitary video pulses. A universal relation is found linking the minimum possible duration of a breatherlike pulse with the medium parameters. It is shown that such a pulse contains roughly one and a half periods of the light-wave. Zh. éksp. Teor. Fiz. 111, 404–418 (February 1997)