This paper obtains the exact 1-soliton solution of the complex GinzburgLandau equation with power law nonlinearity that governs the propagation of solitons through nonlinear optical fibers. The technique that is used to carry out the integration of this equation is He’s semi-inverse variational principle.

We argue that the integrable modified nonlinear Schrödinger equation with the nonlinearity dispersion term is the true starting point to analytically describe subpicosecond pulse dynamics in monomode fibers. Contrary to the known assertions, solitons of this equation are free of self-steepening and the breather formation is possible.