Gain-Managed Nonlinear Amplification in a 97.7-MHz Dissipative Soliton Figure-9 Fiber Laser

In this work, we demonstrate a gain-managed nonlinear (GMN) amplification system based on a dissipative soliton (DS) figure-9 fiber laser with a fundamental repetition rate around 100 MHz. The influence of different combinations of waveplates on the realization of DS mode-locking in the figure-9 laser is first explored through numerical simulation, after which the stable mode-locking of the figure-9 fiber laser with a repetition rate of 97.7 MHz is experimentally obtained. Additionally, we discuss the different lengths of gain fiber on the spectral flatness of GMN amplification, with numerical simulation results that agree well with the experimental results. With those efforts, femtosecond pulses with an energy of 10 nJ, a pulse width of 45 fs, and a peak power of 0.2 MW are obtained with the optimized length of gain fiber. It is anticipated that this broadband, high-repetition-rate femtosecond fiber source holds great potential for applications in biomedicine and industry.