Recent advances in nanosecond-pulsed Ytterbium-doped all-fiber lasers

Ytterbium-doped all-fiber nanosecond-pulsed lasers have developed rapidly in recent years and have opened up new horizons in many fields. Especially in the field of laser cleaning, there is a strong demand for nanosecond pulsed fiber laser with high-power and high-energy. Multi-channel fiber laser beam combining is the main means to achieve high-power and high-energy laser output. The complexity of the structure depends on the output characteristics of a monolithic laser. Improving the output characteristics of monolithic nanosecond pulsed all-fiber laser is very important for laser cleaning and other applications. In this paper, the research progress of monolithic Ytterbium-doped all-fiber nanosecond pulsed lasers is summarized, and the main factors that limit its power and energy expansion are analyzed. Firstly, the recent advances of nanosecond pulsed Ytterbium-doped all-fiber oscillator is reviewed with active Q-switching, passive Q-switching and gain-switching technology. Then, the research status of nanosecond pulse Ytterbium-doped all-fiber amplifiers is summarized with large pulse energy, high average power and collaborative development of the two. In the end, the development trend of Ytterbium-doped all-fiber laser in scaling of power and energy is prospected from the factors limiting the output characteristics.