Silicon in-phase/quadrature modulator with on-chip optical equalizer

We report an in-phase/quadrature modulator with on-chip optical equalizer in a silicon photonic circuit, capable of generating 56-Gbaud quadrature-phase-shift-keyed signals. The equalizer provides a 2.5-dB improvement in optical signal-to-noise ratio at bit-error ratio of 2.4×10 ^-2 .