Analysis of External CW Optical Injection for Timing Jitter Reduction of Actively Mode-Locked Lasers

Actively and harmonically mode locked lasers (AHMLL) have been extensively studied as an optical clock source for photonic-assisted analog-to-digital conversion of broadband RF signals. Such lasers can generate high repetition rate pulse train with ultralow timing jitter [1]. The optical injection of AHMLL has been shown to be an interesting way to reduce the supermode noise, which is an important source of residual phase noise at high offset frequency [2]. Although efforts have been put to stabilize the external seed laser on a longitudinal mode of the AHMLL [3], no study on the impact of seed laser parameters have been reported. We present here our first results on the parametric study of a CW-injected AHMLL to understand better the evolution of the laser performance under different power and optical gain conditions.