设计并实验研究了一种结构简单的主动调制锁模高重复频率窄脉宽光纤激光器。采用窄线宽连续激光调制4 GHz高重频后, 通过拉曼增益孤子压缩效应将脉宽由27 ps压窄至2.6 ps。该高重频锁模激光泵浦一段300 m长高非线性光纤, 同时脉冲被展宽至7.4 ps。产生的超连续谱平坦度20 dB宽带可达250 nm, 功率波动为±0.2 dB。

A simple high repitition-rate mode-locking fiber laser with narrow pulse width based on active modulation was designed and studied experimentally. A narrow linewidth continuous wave laser was modulated by a modulator with 4 GHz repetition-rate, and then, the pulse width can be narrowed to 2.6 ps from 27 ps by Raman gain soliton compression. The high repetition-rate mode-locking fiber laser was used to pump a 300 m long high nonlinear fiber, and the pulse width was extended to 7.4 ps. This supercontinuum (SC )has better flatness (a 250 nm SC spectrum can be observed at 20 dB) and higher stability (power fluctuation can be ±0.2 dB).