Stable all-fiber photonic temporal differentiator using a long-period fiber grating interferometer

A novel configuration of all-fiber photonic temporal differentiator optimized for tens-of-gigahertz processing bandwidth is suggested and experimentally demonstrated. This device covers the gap in terms of processing bandwidth between the two previously-demonstrated all-fiber designs, namely the fiber Bragg grating-based differentiator (<20 GHz) and that based on a uniform long-period fiber grating (>100–200 GHz).