Evolution of a solitary pulse in the cubic complex Ginzburg-Landau (CGL) eq
uation, including third-order dispersion (TOD) as a small perturbation, is
studied in detail. Starting from the exact Pereira-Stenflo soliton solution
, we develop analytical approximations which yield an effective velocity c
of the pulse induced by TOD. The analytical predictions are compared to dir
ect numerical simulations, showing acceptable agreement at small values of
the TOD parameter, provided that the second-order dispersion coefficient D
takes values D > -3/2 or D < -30 (very different analytical approximations
are used in these two cases). Between these regions, the numerically found
dependence c(D) shows a very steep jump at D congruent to -3/2, and a less
steep jump in the opposite direction at -30 < D < -20, each jump changing t
he sign of the velocity. The simulations also demonstrate that there is a m
aximum of the laminar propagation distance (before the onset of the ultimat
e turbulent stage) attained at D congruent to -18. The action of the slidin
g-frequency filtering on the soliton dynamics is also investigated numerica
lly, and it is found that it slightly increases the laminar propagation dis
tance.