Subpicosecond pulse generation at 134 GHz using a quantum-dash-based Fabry-Perot laser emitting at 1.56 mu m

We demonstrate passive mode locking in one-section monolithic semiconductor laser diodes based on quantum-dash active layer at very high repetition rate in the 1.5 mu m window. Transform-limited pulses are generated at 134 GHz with subpicosecond width, without any pulse compression scheme. A 50 kHz linewidth of the radio-frequency spectrum is also demonstrated at 42 GHz, the lowest value reported for any passively mode-locked semiconductor laser. We further show that the saturable absorption section in two-section devices has no significant impact on the mode-locking behavior.