Passive and Hybrid-State Operation of High-Order Harmonic Colliding Pulse Mode-Locked Laser

We present a colliding pulse mode-locked semiconductor laser operating in the third-harmonic mode-locked state. In passive mode-locking operation, it achieved a repetition rate of 15.4 GHz and a 2.7 ps transform-limited sech-pulse. In hybrid mode-locking operation, the linewidth decreased from 43.327 MHz to 0.753 kHz, and the timing jitter reduced from 11.052 ps to 0.475 ps.