INTERACTIONS BETWEEN FEMTOSECOND SOLITONS IN OPTICAL FIBERS

Interactions between two femtosecond solitons or solitonlike pulses in single-mode optical fibers are studied. Because of Raman scattering, the total energy of the two input pulses is redistributed into two new solitons. The energy redistribution is controlled by various input parameters. The particular dependences on the initial values of relative phase, pulse separation, relative intensity, and wavelength separation are investigated. Numerical simulations are performed through a solution of the generalized nonlinear Schrodinger equation with the use of a modified version of the beam-propagation method. It is found that the interaction between the two pulses is determined by the interplay among the interpulse Raman scattering, the Raman self-frequency down-shift, the cross-phase modulation, and the walk-off effect. The energy redistribution between the two interacting pulses has potential applications to ultrafast switching devices and logic gates.