Fractional-order photonic differentiator using an on-chip microring resonator

A tunable temporal photonic fractional differentiator using a silicon-on-isolator (SOI) electrically tuned microring resonator (MRR) is proposed and experimentally demonstrated. Through changing the voltage applied on the MRR, the fractional order of the photonic differentiator can be continuously tuned. The proposed fractional-order differentiator is demonstrated experimentally with Gaussian pulse injection and rectangular pulse injection, respectively. The small deviation shows the feasibility of our photonic differentiator with an integrated silicon MRR.