Abstract

A valuable advantage of semiconductor optical amplifiers over rare-earth-doped fiber amplifiers is their flexibility as they cover a wide wavelength range from 0.7 to 1.6 μm. Semiconductor amplifiers working at 1.3 μm are considered to be real candidates for upgrading the existing links made of step-index fiber with zero dispersion at 1.3 μm to higher bit rates. One of the basic problems in high- bit rate fiber communication and storage systems on the base of semiconductor amplifiers is the problem of asymptotic stability of solitary wave used as information bit. Equation describing the dynamics of a pulse in communication line with semiconductor amplifiers was shown to have exact solitary wave solution of hyperbolic secant type with hyperbolic tangent chirp.¹ However this secant pulse is, generally speaking, asymptotically unstable solitary wave; some numerical examples of its instability was shown in Ref. 1. Consequently one can hardly develop the communication system based on the hyperbolic secant solitary wave as an information bit.²

© 1996 Optical Society of America