摘要
We derive nonlocal coupled-mode equations for a Bragg grating embedded in a medium with nonlocal nonlinearity. Using these equations, we study the oscillatory instability of nonlocal Bragg solitary waves and demonstrate that collisions between them result in fusion into a standing pulse (or breather), possibly with generation of additional jets, in a broad range of parameters. The results are explained by considering the effect of spatial dispersion induced by the nonlocal nonlinear response.