InGaAs quantum-dot mode-locked laser diodes

This paper presents a selection of recent advances on two-section passively mode-locked InGaAs-based quantum-dot laser diodes. Pulse generation is demonstrated for repetition rates ranging from 310 MHz to 240 GHz, and with pulse durations ranging from the picosecond to the sub-400 fs regime. Mode-locking trends in these devices are discussed, and device performance improvements in terms of pulse duration, output power, and noise properties are presented. Design rules for reducing the pulse duration, increasing the output power, and improving noise performance are outlined. Implementation of tapered waveguide structures yields significant performance improvements, allowing the simultaneous achievement of ultrashort, Fourier-limited pulse generation with low amplitude noise, low timing jitter, and narrow RF linewidths.