We propose and demonstrate a method to generate a flat broadband chaotic laser by using an active optical feedback loop combined with a high nonlinear fiber. The feedback strength and nonlinear effect, especially the four-wave mixing effect of high nonlinear fiber, are studied to improve the bandwidth and flatness of chaos. When the feedback strength is 6.6 and injected fiber power is 1.0 W, a chaotic signal with a frequency range over 50 GHz, 80% bandwidth of 38.9 GHz, and flatness of 4.2 dB are experimentally achieved.

中文翻译：

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有源光反馈回路结合高非线性光纤产生宽带混沌激光器

我们提出并演示了一种通过结合高非线性光纤的有源光反馈环路来生成扁平宽带混沌激光器的方法。研究了反馈强度和非线性效应，特别是高非线性光纤的四波混频效应，以改善混沌的带宽和平坦度。当反馈强度为6.6，注入的光纤功率为1.0 W时，通过实验可获得频率范围超过50 GHz，80％带宽为38.9 GHz且平坦度为4.2 dB的混沌信号。