Effects of dispersion and saturable nonlinearity on dissipative solitons

We study the properties of an intense pulse propagating in dissipative nonlinear systems considering nonlinear dispersion within the framework of the variational approach. We model the system by the so-called saturable cubic-quintic nonlinear Schrodinger equation including perturbing terms like two-photon absorption, intra-pulse Raman scattering, and dissipative losses. Introducing Rayleigh's dissipative function we derive a set of coupled differential equations for the various parameters of the pulse. It is clearly demonstrated how the interplay among dispersion, saturable nonlinearity, and dissipative losses affects intense-short pulse propagation in optical media.