Vector Effects of Dissipative Soliton in All-Fiber MOPA System

The performance of seed laser source will have a great impact on the output pulse quality of the master oscillator power amplifier (MOPA) system. Here, we report the influence of the soliton vector features on the pulse uniformity in an all-fiber MOPA configuration. We demonstrated that, although the intensity of the dissipative soliton seed source is uniform, the intensity of the output pulse train from the MOPA will show fluctuations if the soliton polarization state is not locked, i.e., polarization-rotating vector soliton. It is found that the appearance of non-uniform pulse intensity is caused by the combination of the polarization instability and the polarization dependent gain in the polarization maintaining fiber amplifier. The obtained results indicate that the polarization evolution of seed pulsed source is critical to generation of stable pulse train from the MOPA, and also might be useful to the communities dealing with solitons and high-power pulsed fiber lasers.