Monolithic Passively Mode-Locked Lasers using Quantum Dot or Quantum Well Materials Grown on GaAs Substrates

In this work, the optical characteristics of monolithic passively mode-locked lasers (MLLs) fabricated from 1.24-μm InAs dots-in-a-Well (DWELL), 1.25-μm InGaAs single quantum well (SQW), and 1.55-μm GaInNAsSb SQW structures grown using elemental source molecular beam epitaxy (MBE) are reported. 5 GHz optical pulses with subpicosecond RMS jitter, high pulse peak power (1W) and narrow pulse width (< 10 ps) were demonstrated in monolithic two-section InAs DWELL passive MLLs. With the 42% indium InGaAs SQW MLL, a record high-temperature performance for a monolithic passively mode-locked semiconductor laser is found. Compared with the typical operating range of the InAs DWELL devices (<60°C), the operation is in excess of 100 °C. The first 1.55-μm GaInNAsSb SQW MLL operates at a repetition rate of 5.8 GHz and has a 3-dB bandwidth of 170 kHz in the RF spectrum indicating respectable jitter.