Synchronously mode-locked fiber laser based on parametric gain modulation and soliton shaping

Abstract

A novel synchronously mode-locked fiber laser is demonstrated by combining the parametric gain modulation in a pulse-pumped nonlinear optical loop mirror (NOLM) with the soliton shaping property of a nonlinear amplifying loop mirror (NALM). Parametric gain modulation induced by the synchronous pump pulses within the NOLM starts and defines the timing of the mode-locked signal pulses, while the nonlinear intensity discrimination in the NALM stabilizes the mode-locked pulses and optimizes their shapes. A stream of 1.3 ps transform-limited soliton pulses is generated when the NOLM is pumped by a mode-locked fiber laser. Moreover, we find that the timing jitter of the synchronously mode-locked pulse train is suppressed by more than 10 dB when compared to the pumping laser.