Abstract

The fundamental soliton¹ is a pulse of shape and peak Intensity such that effects of index nonlinearity always exactly cancel dispersive broadening; thus, in the limit of zero loss, the pulse width and shape remain constant with propagation. Although loss is certainly not negligible In long fiber spans, by using Raman gain² to offset such loss, it may be possible to create a long-distance communications system based on soliton propagation.^3,4 This possibility is based on the fact that in the right conditions, when such distributed gain is used to recover the energy of fundamental solitons, their pulse widths are restored as well.

© 1985 Optical Society of America