Efficient structure for optical interleavers using superimposed chirped fiber Bragg gratings

This letter presents an all-fiber structure to implement optical interleaver by using superimposed chirped fiber Bragg gratings and a fiber coupler. With the proposed structure, a flat-top 25/50-GHz interleaver is experimentally fabricated and demonstrated with a 0.5-dB passband bandwidth of 17.1 GHz, a channel isolation of 20 dB, and group delay variations of 10 ps in the 0.5-dB passband.