Silicon In-Phase/Quadrature Modulator With On-Chip Optical Equalizer

Silicon photonics has technical advantages allowing for large-scale optical integrated circuits due to both the nature of high-index-contrast silicon waveguides and the mature fabrication processes. Recent advances in this field have shown remarkable monolithic integration capabilities for both passive and active optical components on the same chip. In this paper, 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 2.5-dB improvement in optical signal-to-noise ratio at a bit-error ratio of $2.4 \times 10^{-2}$ .