Pulse Timing Jitter Estimated From Optical Phase Noise in Mode-Locked Semiconductor Quantum Dash Lasers

The determination of timing jitter obtained from optical phase noise measurements is investigated in InAs/InP quantum dash Fabry-Pérot mode-locked coherent comb lasers with different pulse repetition rates. The results are compared with those determined through a direct measurement of the first harmonic of the RF power spectrum. Very good agreement is achieved. The ability to measure the timing jitter from optical phase noise is not restricted by the repetition rate of the laser being studied, allowing it to be applied to extremely high repetition rate lasers. Using these lasers we demonstrate 5.4 Tbit/s (PAM-4 48 × 28 GBaud PDM) and 10.3 Tbit/s (16 QAM 56 × 23 GBaud PDM) aggregate data transmission capacity. The ultra-low timing jitter exhibited by these devices make them excellent sources for multi-terabit optical networks.