Internal Bandwidth Equalization in a CMOS-Compatible Si-Ring Modulator

Bandwidth equalization using a simple complementary metal-oxide-semiconductor-compatible tunable silicon-ring modulator is shown. We demonstrate >35-GHz small signal bandwidth and use the resonator to mitigate bandwidth limitations from other measurement system components. Configuring the optical carrier to be off resonance within the ring free-spectral range allows high-frequency enhancement and low-frequency suppression of the S21parameter to achieve system response equalization. Our results suggest that the carrier and modulation sidebands can have very different transient characteristics within the ring modulator.