Abstract

Recently,¹ we proposed the use of solitons at the zero dispersion point for long-haul communication, a scheme that combines the low-power requirement of propagation at the zero dispersion point with the robustness of the soliton approach. Important issues, such as the variation of the zero dispersion point along the fiber length, were not considered. In a fiber, the zero dispersion point along the fiber length was not considered. In a fiber, the zero dispersion point fluctuates due to variations in the fiber core size. By using a multi ple-length scale expansion, we are able to show analytically that if the correlation length of the axial inhomogeneities is much smaller than both the second-order and third-order dispersion length, solitons propagate in this regime even if the magnitude of the fluctuations is large. Physically, the variations are so fast that the pulse cannot respond to them. The analysis is supported by results of numerical simulations. We have also investigated the effect of Raman downshift, which affects solitons by shifting the carrier wavelength away from the zero dispersion point.

© 1987 Optical Society of America