Observation of timing jitter reduction induced by spectral filtering in a fiber laser mode locked with a carbon nanotube-based saturable absorber.

A self-starting passively mode-locked fiber laser with a carbon nanotube-based saturable absorber and a fiber-based bandpass filter (BPF) is proposed. Incorporation of a BPF into the cavity leads to a great reduction of its timing jitter from 84.8 to 29.1 fs (10 Hz-3 MHz). This happens because the filtering effect can weaken the fluctuation of the central wavelength induced by the quantum noise, being one of the important contributions to timing jitter in the optical amplifying process.