A Silicon Photonic RF Phase Shifter With Linear Phase Response and Low RF Power Variation

We propose and experimentally demonstrate a microwave photonic phase shifter based on a tunable silicon photonic interleaver. This device consists of a microring resonator, a tunable interleaver, and a 2 × 1 multimode interferometer (MMI). By thermally tuning the interleaver, a linear phase shift of 188° is realized with a linearity of 0.08 and a radiofrequency (RF) power variation within 1 dB for a 40-GHz signal.