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 the nonlinear Schrodinger solitons in that Bragg solitons attract or repel each other, depending on their relative phases. However, the relative phase between two Bragg solitons is found to depend on their initial separation. We discuss the implications of the numerical results for laboratory experiments. (C) 1999 Optical Society of America. [S0740-3224(99)01301-6]. OCIS codes: 060.0060, 060.2310, 190.4370, 190.5530, 350.2770.