Comprehensive Theoretical and Experimental Study of Short- and Long-Term Stability in a Passively Mode-Locked Solitonic Fiber Laser

We demonstrate the short- and long-term stable operation of an all-polarization-maintained Fabry–Pérot cavity passively mode-locked fiber laser. The laser operates in an all-anomalous-dispersion solitonic regime. Laser stability is studied by a variety of measurements, which confirm the high stability of the laser in the temporal and spectral–both optical and electrical-domains. Pulse durations of 540 fs, period-relative time jitters of
$\sim$
0.015‰, and long-term uninterrumped operation with 0.4% variation (standard deviation) in the average output power are obtained. The highly stable operation of the laser oscillator was maintained after amplifying the laser output with a conventional EDFA. Pulse durations of
$\sim$
244 fs, period-relative time jitters of
$\sim$
0.019‰,  and an average output power of 20 mW were obtained after amplification, while maintaining the 100-dB signal-to-noise ratio of the laser oscillator measured at 500-Hz offset from the fundamental harmonic frequency. The theoretical validation of our experimental results is based on solutions of the Nonlinear Schrödinger Equation. We demonstrate that wavelength and
z
-position dependences of the active medium gain must be taken into account for an accurate correspondence with the experimental properties of the laser.