We report on a robust, erbium-doped ultrafast fiber laser mode-locked by an artificial saturable absorber (SA) based on nonlinear polarization evolution (NPE). Unlike previous NPE fiber lasers, our cavity employs all polarization-maintaining (PM) fiber so that the laser is insensitive against environmental fluctuations. By incorporating a phase shifter in the NPE artificial SA, the oscillator possesses self-starting mode-locking ability. However, it is difficult to start pulsed operation without such a phase shifter. The simple and novel fiber laser scheme utilizing above mentioned design can directly generate 0.11 nJ, 1.20 ps ultrashort pulses at a repetition rate of 115 MHz, which is the highest repetition rate in this type of fiber lasers. We believe that this fiber oscillator offers a promising source for high repetition rate applications under less stable conditions.

中文翻译：

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使用所有保偏光纤的115MHz线性NPE光纤激光器

我们报告了一种基于非线性偏振演化（NPE）的，由人造可饱和吸收剂（SA）锁模的坚固，掺-的超快光纤激光器。与以前的NPE光纤激光器不同，我们的腔采用了所有偏振保持（PM）光纤，因此该激光器对环境波动不敏感。通过在NPE人工SA中集成移相器，振荡器具有自启动锁模能力。但是，如果没有这种移相器，则很难开始脉冲操作。利用上述设计的简单新颖的光纤激光器方案可以以115 MHz的重复速率直接生成0.11 nJ，1.20 ps的超短脉冲，这是此类光纤激光器中最高的重复速率。