实验研究了基于掺Yb3+单偏振大模场面积光子晶体光纤的高单脉冲能量光纤飞秒激光放大器。该放大器为非线性放大,利用自相位调制实现非线性相移得到光谱展宽。由于压缩器提供适当的色散补偿,并优化振荡-放大系统中的增益、非线性、高阶色散参数,使得压缩后脉冲具有较高的峰值功率。同时利用声光调制器降低振荡级的重复频率到1 MHz,最后得到最短脉冲宽度124 fs,单脉冲能量1.56μJ,对应峰值功率12.6 MW的激光输出。 The high monopulse energy fiber femtosecond laser amplifier based on Yb3 + single mode PMF photonic crystal fiber was experimentally studied. The amplifier for the nonlinear amplification, the use of self-phase modulation to achieve nonlinear phase shift spectrum broadening. Since the compressor provides proper dispersion compensation and optimizes gain, nonlinearity, and higher-order dispersion parameters in the oscillation-amplification system, the compressed pulse has a higher peak power. At the same time, the acousto-optic modulator is used to reduce the repetition frequency of the oscillation stage to 1 MHz. Finally, the shortest pulse width is 124 fs, and the single pulse energy is 1.56 μJ, corresponding to the laser output with the peak power of 12.6 MW.