Interaction of Bragg Solitons in Fiber Gratings

We investigate numerically the interaction between two copropagating Bragg solitons in a fiber grating. We find that in the low-intensity limit, the interaction is reminiscent of nonlinear Schrodinger solitons in that Bragg solitons attract or repel, depending on their relative phases with the difference that the relative phase between two Bragg solitons depends on their initial separation. We discuss the implications of the numerical results for laboratory experiments.