The effect of pulse walkoff on bright pulse compression by dark soliton in optical fibers

The effect of pulse walkoff on the compression of bright optical pulses by dark solitons in single-mode fibers is analyzed by numerically solving the coupled amplitude equations describing the evolution of two copropagating pulses. The results show that even a small walkoff between the bright pulse and the dark soliton can exert severe influence on the bright pulse compression. The compressed bright pulse is longer with a lower peak power when walkoff is taken into account. Furthermore, the compressed bright pulse is asymmetric and the optimum fiber length is found to be longer than that expected in the absence of pulse walkoff.