Abstract

Erbium-doped fiber amplifiers(EDFAs) can be used to amplify solitons for long- haul transmission[1] or to reshape solitons[2]. When a very-short soliton evolves through an EDFA, if the gain per soliton period(GPSP) of the EDFA is large, before the nonlinearity takes effect the amplitude of the soliton pulse is amplified whilst the shape remains unchanged. After passing through some distance, the increase in amplitude renders the effect of non-linearity significant so that the amplified soliton pulse(ASP) becomes narrower and at the same time the amplitude increases even faster. Comparing the shape of the ASP with that of the fundamental soliton with the same amplitude(FSWSA), we may find that for a certain length of the EDFA the shape of the ASP best fits the shape of the FSWSA. This paper shows that such a length of the EDFA does indeed exist and analyses are provided of how this length and the shape of the ASP changes with the gain and the gain dispersion of an EDFA are also provided.

© 1992 Optical Society of America