A 6 x 30 Gb/s Tunable Transmitter PIC with low RF Crosstalk from an Open-Access InP Foundry

We demonstrate a six-channel tunable optical transmitter photonic integrated circuit fabricated in an open-access indium phosphide foundry process. The device monolithically integrates 20-nm tunable lasers and 30-Gb/s Mach–Zehnder modulators, without the use of Bragg gratings or quantum wells for phase modulation, to form a compact ${\text{3.9}} \times {\text{4.5 mm}}^{2}$ high-density $\text{6} \times \text{30}$  Gb/s parallel transmitter. It exhibits a capacity density metric of 10 Gb/s/ $\text{mm}^2$ , comparable to the state-of-the-art results from the literature and low $  dB inter-channel radio-frequency crosstalk. With an attractive price point of 7 USD/Gb/s, the device can be a low-cost solution for data center interconnects or residential access networks.