A two-parameter family of single- and multiple-hump solitary waves in a fiber transmission line with periodically aligned semiconductor optical amplifiers and fixed in-line filters can be identified, provided that the dispersion length considerably exceeds the spacing period and that the average-soliton concept can be adopted. These solitary waves are robust against fluctuations of the input amplitude. We show that the finite gain recovery time of the amplifier leads to the formation of topological solitons. Multiple-hump solutions decay into pulses with equal amplitudes if the dispersion length is comparable with the amplifier spacing.
© 1999 Optical Society of America
(060.4510) Fiber optics and optical communications : Optical communications
(190.4370) Nonlinear optics : Nonlinear optics, fibers
(190.5530) Nonlinear optics : Pulse propagation and temporal solitons
(190.5970) Nonlinear optics : Semiconductor nonlinear optics including MQW
M. Gälles, I. M. Uzunov, and F. Lederer, "Robust solitary waves in fiber transmission lines with semiconductor optical amplifiers," J. Opt. Soc. Am. B 16, 689-694 (1999)