基于自相似光纤激光放大技术,通过非线性光谱展宽突破光纤增益带宽的限制,结合高效色散补偿以获得高功率超短脉冲放大输出,最终得到中心波长1030 nm、重复频率40 MHz、平均功率34 W、脉冲宽度50 fs的高质量脉冲输出,对应峰值功率17 MW。该系统采用可饱和吸收体锁模,采用啁啾光纤布拉格光栅补偿腔内色散,相对于啁啾脉冲放大技术具有结构简单、集成度高等优点。实验结合光纤热管理技术和数字测控技术(FPGA),显著提升了系统的稳定性和鲁棒性,极大推动了高功率飞秒光纤激光在下游诸多科学与技术领域的应用。

In this work, self-similar fiber laser amplification technology and nonlinear spectrum broadening are employed to overcome the gain limitation of the fiber. Using high-effectivity dispersion compensation, a high-quality pulse with the pulse width of 50 fs, average power of 30 W, central wavelength of 1030 nm, and repetition rate of 40 MHz, corresponding to a peak power of 17 MW, is realized. The system employs a saturable absorber for mode locking and chirped fiber Bragg grating for dispersion compensation in the cavity. In comparison with a chirped pulse amplification system, the proposed system has the advantages of simple and high integration. The stability and robustness of the proposed system are greatly improved through fiber thermal management technology and field programmable gate array (FPGA), which significantly promotes the applications of high-power femtosecond fiber lasers in many mainstream fields of sciences and technology.