InP-based Monolithic Mode-Locked 40 GHz Lasers for High-Speed Transmission Systems Utilizing Phase Modulation Formats

The development of compact 40 GHz pulse laser modules with a monolithic InP-based mode-locked 1.55 mum / 40 GHz MQW DBR laser chip inside is reported. The chip architecture and its optimization as well as the main fabrication challenges arising from the requirement of meeting standardized pulse frequencies and high laser chip yield are outlined. The excellent module performance data are emphasized and in particular discussed with respect to the applicability in high speed optical communication systems based on phase sensitive modulation formats like D(Q)PSK.