We demonstrate a novel, robust and compact fiber laser mode-locked by nonlinear polarization evolution (NPE) in polarization-maintaining (PM) fibers. The reflectivity of the artificial saturable absorber (SA) is analyzed to explain the mode-locking mechanism in the laser cavity. Experimentally, three linear laser schemes that feature repetition rates 94 MHz, 124 MHz and 133 MHz are systematically investigated. When the pump power is 1100 mW, the 124-MHz laser cavity delivers highly stable pulses with a single-pulse energy of 0.92 nJ. After the compression, the pulse duration obtained from the 124-MHz fiber laser is 250 fs, while the corresponding transform-limited pulse duration is 124 fs. The highest fundamental repetition rate that could be achieved in our experiment is 133 MHz, as mentioned above. The noise characterization has been performed with different cavity lengths and therefore different net-cavity dispersion. The 68-fs timing jitter and the 0.01% relative intensity noise (RIN) of the 133-MHz fiber laser have been realized integrated from 1 kHz to 10 MHz. Furthermore, the root-mean-square (RMS) power fluctuation is 0.35% in 2 hours, which implies superior stability of the output power. Thus, this linear fiber oscillator provides a competitive low-noise light source for optical applications appropriate for complex environments.

中文翻译：

---

通过全保偏光纤中的非线性偏振演化锁模的鲁棒新颖的线性光纤激光器


我们展示了一种新颖、坚固且紧凑的光纤激光器，通过保偏 (PM) 光纤中的非线性偏振演化 (NPE) 进行锁模。分析人工可饱和吸收体（SA）的反射率，以解释激光腔中的锁模机制。在实验上，系统地研究了重复频率为 94 MHz、124 MHz 和 133 MHz 的三种线性激光器方案。当泵浦功率为1100 mW时，124 MHz激光腔可输出高度稳定的脉冲，单脉冲能量为0.92 nJ。压缩后，124 MHz光纤激光器获得的脉冲持续时间为250 fs，而相应的变换限制脉冲持续时间为124 fs。如上所述，我们的实验中可以实现的最高基本重复率为 133 MHz。噪声特性是在不同的腔长度以及不同的净腔色散下进行的。 133 MHz光纤激光器的68 fs定时抖动和0.01%相对强度噪声（RIN）已实现从1 kHz到10 MHz的集成。此外，2小时内均方根（RMS）功率波动为0.35%，这意味着输出功率具有出色的稳定性。因此，该线性光纤振荡器为适合复杂环境的光学应用提供了具有竞争力的低噪声光源。