We have successfully compressed the pulse duration of an all-normal-dispersion (ANDi) Yb-fiber laser to sub-100 fs by a single-mode nonlinear fiber amplifier. Through optimizing the input power, prechirp, and the pump power of the amplifier, the pulse duration of the ANDi Yb-fiber laser is compressed to 68 fs when a 2.5-m active fiber is used, although for a 3.5-m active fiber, the pulse duration of the laser can be compressed to 58 fs. We have also shown that a low relative intensity noise is maintained within the nonlinear amplification process. The experimental results prove this ultrashort-pulse-duration and low-noise laser source with moderate output power can be a good candidate for frequency comb, multiphoton imaging, coherent Raman spectroscopy, and other applications.

中文翻译：

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单模光纤放大器对全正色散Yb光纤激光器的非线性脉冲压缩

我们已经通过单模非线性光纤放大器成功地将全正色散（ANDi）Yb光纤激光器的脉冲持续时间压缩到100 fs以下。通过优化输入功率，前置调频和放大器的泵浦功率，当使用2.5 m有源光纤时，ANDi Yb光纤激光器的脉冲持续时间被压缩至68 fs，尽管对于3.5 m有源光纤，激光的脉冲持续时间可以压缩到58 fs。我们还表明，在非线性放大过程中保持了较低的相对强度噪声。实验结果证明，这种具有中等输出功率的超短脉冲持续时间和低噪声激光源可以很好地用于频率梳，多光子成像，相干拉曼光谱等应用。