Existencia y perturbación de solitones ``embebidos'', gobernados por una extensión de la ecuación NLS

Abstract

We determine the conditions for the existence of ``embedded solitons'' (ES), and conventional bright and dark pulses, in an extension of the cubic nonlinear Schrödinger (NLS) equation with higher-order dispersive and nonlinear terms. The stability of these SE is studied numerically, and it is found that these solitons are semi-stable. The damped oscillatory behavior of the perturbed SE is then analyzed by a variational method, and it is shown that this damping is a consequence of the emission of radiation. Finally, it is shown that the uniqueness of these SE is due to a delicate balance between nonlinearity and dispersion.