Progress in InP-based photonic components and sub-systems for digital coherent systems at 100Gbit/s and beyond

Digital coherent technology has enabled a new generation of WDM transmission systems with increased capacity and robust performance. We review recent progress in InP-based photonic components and sub-systems to enable cost-effective, compact and scalable new transceiver solutions for 100Gbit/s and beyond, and discuss future directions and challenges.