Variable-in, Variable-out Optical Clock Recovery With an Optically Injection-Locked and Regeneratively Actively Mode-Locked Laser Diode

A novel method of variable-in, variable-out optical clock recovery using a monolithic mode-locked laser diode (MLLD) is proposed for future advanced and adaptive photonic networks. This method is based on regenerative active mode locking of the MLLD simultaneously optically injection-locked with an external seeding light and enables variable-in, variable out optical clock recovery in terms of variable wavelengths of input data light and recovered optical clock. The proposed method was experimentally validated at 40-Gbps optical clock recovery experiments. Stable clock recovery was successfully demonstrated, retaining almost unchanged pulse characteristics of the recovered optical clock pulses including low timing jitter (<;0.3 ps) and low frequency chirping, even when the wavelengths of the input data and the output clock were widely changed by over 30 nm (1535 nm to >;1570 nm).