Fractal dependence of vector-soliton collisions in birefringent fibers

Vector-soliton collisions in birefringent nonlinear optical fibers are inve stigated. The underlying mathematical model is the non-integrable coupled n onlinear Schrodinger equations. It is shown that the exit velocity versus c ollision velocity graph has a fractal structure. When we zoom into differen t positions of this fractal, we get structures which are either a copy, a h orizontal reflection or vertical reflection of the original structure. Coll ision dynamics in the zoomed-in windows and that in the original graph foll ow simple and well-defined patterns as well. We explain this fractal depend ence of the collision by a novel resonance mechanism between translational motion of vector solitons and radiation modes which cause internal oscillat ions inside a vector soliton. (C) 2001 Published by Elsevier Science B.V.