Low-power continuous-wave (cw) pumped supercontinuum sources exhibit poor spectral flatness and high sensitivity to the position of pump-wavelength with respect to the zero-dispersion of the nonlinear fiber. We propose a technique to overcome these limitations by the simple addition of a section of transmission fiber (such as Corning LEAF) before the nonlinear broadening stage. The pump incoherence introduced by this fiber in the C-band allows for a smooth, equalized, input wavelength flexible supercontinuum at low powers. With the proposed two-stage spectral broadening, we have successfully demonstrated for the first time, a cw pump wavelength agile all-fiber supercontinuum module with spectra spanning from 1300 nm to 2000 nm using relatively short lengths of nonlinear fiber. Similar supercontinuum is obtained for output powers from 80 mW up to a maximum in this work of 550 mW making it an ideal source for broadband low-power applications.

中文翻译：

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泵浦波长灵活、连续波光纤超连续谱使用两级光谱展宽

低功率连续波 (cw) 泵浦超连续谱源表现出较差的光谱平坦度和对泵浦波长相对于非线性光纤零色散的位置的高灵敏度。我们提出了一种技术，通过在非线性展宽阶段之前简单地添加一段传输光纤（例如康宁 LEAF）来克服这些限制。这种光纤在 C 波段引入的泵浦非相干性允许在低功率下实现平滑、均衡、输入波长灵活的超连续谱。通过提出的两级光谱展宽，我们首次成功展示了连续泵浦波长捷变全光纤超连续谱模块，其光谱范围从 1300 nm 到 2000 nm，使用长度相对较短的非线性光纤。