Soliton collisions with wavelength-division multiplexed systems with strong dispersion management

Abstract

We investigate collisions between solitons in a lossless two-channel wavelength-division multiplexed system with strong dispersion management. Numerical results show that the net frequency shift that is due to interchannel collisions is at least 1 order of magnitude smaller than predicted by adiabatic theories. A modified theoretical analysis is presented and shown to be in good agreement with the numerical results.

Collision-induced pulse timing jitter in a wavelength-division-multiplexing system with strong dispersion management

“…This explains why the numerical values of this shift in Ref. 5 were so small. At the same time, the collision-induced position shift is shown to be nonzero and can be obtained in a simple analytical form.…”

“…3 One of the most serious problems in the use of WDM is the cross talk (equivalent to a random timing jitter) induced by collisions of pulses that belong to different channels. Recently the collision-induced frequency shift was considered in several theoretical publications 4,5 by a method developed in Ref. 2 for the sech pulses (see also an early paper 6 in which the cross-talk effect was considered by means of a perturbation theory for the sech solitons in the WDM system).…”

“…However, comparison of these results with direct partial differential equation simulations in the case of strong DM, which has the most promising potential for applications, demonstrates that the actual frequency shift is much smaller than predicted. 5 To reconcile the difference, a phenomenological factor, based on the energy enhancement of a DM soliton, was introduced and shown to work quite well. 5 However, in the regime dominated by DM, when the local dispersion length is much smaller than the nonlinearity length the pulse profile is closer to a Gaussian than to a sech 1,7 (although far tails of the pulses are always exponential rather than Gaussian 8 ).…”

“…5 To reconcile the difference, a phenomenological factor, based on the energy enhancement of a DM soliton, was introduced and shown to work quite well. 5 However, in the regime dominated by DM, when the local dispersion length is much smaller than the nonlinearity length the pulse profile is closer to a Gaussian than to a sech 1,7 (although far tails of the pulses are always exponential rather than Gaussian 8 ). Consequently, in this case the pulse propagates in a nearly linear regime.…”

Soliton Management in Periodic Systems

“…In addition to the above-mentioned benefits of the jitter suppression in DM systems, another strong insensitive to study the soliton dynamics in DM systems is the fact the DM provides for strong suppression of the inter-channel crosstalk, as was first shown in direct simulations of a two-channel DM model reported in paper [134]. Besides that, collisions between solitons in coupled channels is a subject of considerable interest from the viewpoint of the general theory of solitons in periodic strongly inhomogeneous systems.…”