On the spectral sidebands’ evolution of mode-locked fiber lasers

We numerically investigate the role played by small-signal gain, intracavity dispersion, and spectral filtering on spectral sidebands generation and evolution of mode-locked fiber lasers. For a fixed intracavity dispersion, increasing small-signal gain shifts the spectral sidebands toward the central wavelength with enhanced intensities, which results in spectral distortion and soliton pulsation. The wavelength location and intensity of the spectral sidebands can also be manipulated in different operation regimes through the intracavity dispersion variation. On the other hand, spectral filtering significantly influences the soliton pulse formation through the insertion loss and spectral narrowing effects, which affects the properties of the soliton pulses. The obtained experimental results of our proposed mode-locked fiber laser are in consistent with the simulation results achieved from extended vector nonlinear Schrödinger equations.