title: Optical solitons in resonant and nonresonant nonlinear media in the presence of perturbations.
abstract: We studied the optical solitons in nonlinear resonant and nonresonant media in the presence of perturbations, assuming that the transient effects are stimulated by the light scanning beam. We treated a slight deviation from the exact necessary condition for the soliton existence (2betanu=1), as a small perturbation for the integrable system, studying its influence upon the soliton propagation conditions. The approximation is constructed by the help of an algebraic version of the soliton perturbation theory using a Riemann boundary problem in connection with the inverse scattering method. We have obtained the soliton equation and we have solved it in the presence of a small perturbation in the adiabatic approximation. In this case we have demonstrated that for a Lorentz profile line the amplitude of the soliton remains unchanged, the only effect of the perturbation results in a phase shift.
authors.affiliation: Department of Physics, University "Politehnica" Bucharest, Splaiul Independentei 313, Bucharest, 77206, Romania.
authors.forename: M
authors.initials: M
authors.lastname: Piscureanu
authors.forename: D
authors.initials: D
authors.lastname: Manaila-Maximean