Amplitude-noise suppressing mechanism in fiber lasers mode-locked with nonlinear amplifying loop mirror

Abstract

In this work, we investigate steady-states influenced by an inherent amplitude noise-suppressing mechanism in a fiber laser mode-locked with nonlinear amplifying loop-mirror. Based on the interaction of the sinusoidal transmission function with the fluctuating amplitude of the intracavity pulse under specific preconditions, we show that this mechanism leads to a detectable difference of RIN at the reflected and transmitted output. We further enable systematic measurements with a nonlinear fiber-based system that experimentally replicates an isolated roundtrip in the laser. Experimental results and computations clearly show a reduction of the intracavity amplitude fluctuations up to 4 dB for certain steady-states.