Incomplete mode-locking in one-section QD lasers with ultra-long cavity

Semiconductor light emitters based on quantum dot (QD) have recently been used in the fabrication of mode-locked lasers owing to their broad gain spectrum as well as fast carrier dynamics. For GaAs-based InAs QD lasers at 1.3 mum range, mode-locking behaviours of two-section devices with cavity length between 800 and 8000 mum, corresponding to round-trip frequency between 5 and 50 GHz, were investigated to show transform-limited pulses with low uncorrelated timing jitter. While for InP-based InAs QD lasers at 1.5 mum range, self- mode-locking in one-section configuration without saturable absorption was reported to show repetition rate as high as 45 and 134 GHz, corresponding to cavity length of 950 and 340 mum, respectively.