Comparison of timing jitter in external and monolithic cavity mode‐locked semiconductor lasers

A comprehensive timing jitter comparison is made for mode‐locked semiconductor lasers using active, passive, and hybrid mode‐locking techniques in both external and monolithic cavity configurations. Active mode locking gives the lowest residual rms timing jitter of 65 fs (150 Hz‐50 MHz), followed by the hybrid and passive mode‐locking techniques. It is found that monolithic cavity devices with all active waveguides have higher timing jitter levels than the comparable external cavity case.