Localized dispersive states in nonlinear coupled mode equations for   light propagation in fiber Bragg gratings
  Dispersion effects induce new instabilities and dynamics in the weakly nonlinear description of light propagation in fiber Bragg gratings. A new family of dispersive localized pulses that propagate with the group velocity is numerically found and its stability is also analyzed. The unavoidable different asymptotic order of transport and dispersion effects plays a crucial role in the determination of these localized states. These results are also interesting from the point of view of general pattern formation since this asymptotic imbalance is a generic situation in any transport dominated (i.e., nonzero group velocity) spatially extended system. 
C. Martel, M.Higuera, J.D. Carrasco