Propagation Of Soliton-like Pulses Research Articles

Stabilization of Optical Pulse Propagation in a Regime of Ionization and Stimulated Raman Self-Scattering

Dynamics of the propagation of soliton-like pulses in a regime of tunnel ionization and stimulated Raman self-scattering is described analytically. It is shown that the mutual compensation of these effects stabilizes signal parameters. The corresponding formulas for pulse duration are obtained.

Soliton-like pulse propagation in a normal dispersive liquid-core optical fiber.

Soliton-like pulse propagation, where the pulse intensity profile is conserved, except for its trailing edge, is found in a normal dispersive CS2-core optical fiber by a computer simulation. During propagation, it is found that the chirp of a pulse arising from the delayed nonlinear response compensates for the chirp arising from the second-order dispersion near the pulse peak position and the pulse experiences a negative frequency shift and a negative temporal shift. The effects of the instantaneous nonlinear response on the soliton-like pulse propagation are also evaluated, and the calculated spectrum agreed well with the experimental spectrum.

Dispersion tailoring and soliton propagation in silicon waveguides

The dispersive properties of silicon-on-insulator (SOI) waveguides are studied by using the effective-index method. Extensive calculations indicate that an SOI waveguide can be designed to have its zero-dispersion wavelength near 1.5 microm with reasonable device dimensions. Numerical simulations show that soliton-like pulse propagation is achievable in such a waveguide in the spectral region at approximately 1.55 microm. The concept of path-averaged solitons is used to minimize the impact of linear loss and two-photon absorption.

Soliton formation in a resonant amplifying—absorbing medium

Self-formation of one or several soliton-like pulses from a nonsoliton powerful laser pulse during its propagation through a two-component resonant amplifying—absorbing medium with an energy dissipation channel is studied numerically. Both components of the medium are simulated by two-level particles. Homogeneous mixtures of these components and media with consecutive amplifying and absorbing layers are considered. A qualitative analysis of the results is based on a simplified model of the process of soliton-like pulse propagation.

Spatiotemporal bright soliton Y junctions in nonlinear planar waveguides

The splitting and steering of ultrashort pulses propagating through a Kerr medium are investigated. This investigation extends earlier ones of cw spatial soliton Y junctions into the area of subpicosecond solitonlike pulse propagation. Besides that of the all-optical steering process, the influence of normal group-velocity dispersion and two-photon absorption is discussed. It is found that both processes modify the transmission characteristics of the system (i.e., output versus input beam intensity) in a similar way. However, two-photon absorption inhibits the steering property of Y junctions, whereas normal group-velocity dispersion enhances it. A model based on an adiabatic propagation approximation is used to explain this behavior qualitatively.

Comparisons between Maxwell's equations and an extended nonlinear Schrödinger equation

A model of Maxwell's equations describing the propagation of ultra-short soliton-like pulses in nonlinear dispersive optical media is presented. Asymptotic analysis utilizing a quasi-monochromatic wave approximation is used to reduce these equations to a corresponding extended nonlinear Schrödinger (NLS) equation. Comparisons between numerical solutions of this extended NLS equation and numerical solutions of Maxwell's equations are provided and indicate that this extended NLS equation is a good model for ultra-short soliton-like pulse propagation when the pulse contains less than 10 optical cycles.

Soliton propagation in optical devices with two-component fields: a comparative study

The problem of solitonlike pulse propagation in optical fiber devices with two-component fields is studied. Two examples, viz., propagation of pulses in birefringent optical fibers and in nonlinear couplers, are considered. It is shown that radiation processes play an essential role in the soliton dynamics in two-component field fiber devices. Radiation influences the transformation of the main pulses in different ways in the two cases considered. The influence of radiation is stronger when the soliton is closer to the point of bifurcation or the separatrix and weaker when it is far from it.

Elliptically polarised solitons in birefringent optical fibers

We investigate a soliton-like pulse propagation in birefrigent optical fibres. It is shown that in addition to the fast and the slow linearly polarized stationary solitons there exist stationary elliptically polarized solitons which can propagate without changes of its state of polarisation.

Radiationless optical solitons with oscillating tails

We investigate, analytically and numerically, stationary soliton-like pulse propagation in nonlinear optical fibres, taking into account the effects of fourth order dispersion. A new type of stationary stable soliton-like solution is found. A unique feature of this type of solution is their unusual asymptotic behaviour (oscillating tails).

Dynamics of solitonlike pulse propagation in birefringent optical fibers.

Integrated Stokes parameters are used to describe solitonlike pulse propagation and its state of polarization in birefringent optical fibers. A qualitative analysis on the Poincar\'e sphere is developed to describe the evolution of the state of polarization of the soliton as a whole. Simple analytic equations describing the pulse evolution are derived in the approximation of the average profile. It is shown that two qualitatively different regimes of propagation are possible, depending on the material parameters and on the initial conditions. The approach takes into account the radiation processes. The results of the analytical approach are compared with exact numerical calculations.

Propagation of solitonlike pulses under cross-phase modulation

I identify regions in which different two-soliton combinations can copropagate under cross-phase modulation. Subsoliton-power and supersoliton-power solitons are considered in the context of optical switching. The stability of these pairs to different perturbing factors is also discussed.