Monolithic Tunable Coupled-Cavity WDM Transmitter in a Generic Foundry Platform

We present the monolithic integration of an extended tuning range coupled-cavity laser with travelingwave Mach-Zehnder modulators in a low-cost generic photonic foundry platform for 10 Gb/s operation. Using an intra-cavity Michelson interferometer combined with on-chip reflectors, the coupled-cavity laser shows a tuning range of 25 nm. The modulator building blocks with optimized traveling wave electrodes exhibit efficient modulation and 8.5-GHz electro-optic bandwidth, enabling 10 Gb/s ON-OFF keying. We demonstrate error-free operation of the tunable transmitter in a full photonic circuit environment. The laser modulator combination neither requires Bragg grating formation for wavelength tuning nor additional growth steps for multiquantum-well material in the modulator section and is therefore well suited for cost effective foundry platforms specifically for low-cost applications.