Motion characteristics of Bragg grating solitons in rectangle-apodized fiber Bragg gratings

► We analyze previous researches, and present the novelty. Former reports used point defects to slow down light, but the width of defects must be very narrow, and it is hard to be controlled in the fabrication process. ► In this paper we expand the width of defect and introduce both concave and convex rectangular apodization with a certain width in the middle of gratings to slow or capture light. ► Specially, with the method of convex rectangular apodization, the solitons can get back to the original speed after they pass the apodized region, and this makes it possible to control the delay time in optical communication system. ► Besides, the shape of soliton could be kept better in transmission compared with concave rectangular apodization.