This letter demonstrates the stabilization of an external cavity semiconductor laser at 1550 nm on an ultra-high Q factor fiber ring resonator (FRR). Based on a Pound-Drever-Hall technique, our system is optimized in order to take into account the properties of the FRR which features a large Q factor ( $2\times 10^{9}$ ) but a relatively small free spectral range (2 MHz). The measured performances of the stabilized laser shows a frequency noise level as low as 0.4 Hz²/Hz in the 1 kHz to 10 kHz range and a linewidth lower than 30 Hz for 5 ms integration time.

中文翻译：

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稳定在光纤环形谐振器上的高光谱纯度光源

这封信展示了 1550 nm 外腔半导体激光器在超高 Q 因子光纤环形谐振器 (FRR) 上的稳定性。基于 Pound-Drever-Hall 技术，我们的系统进行了优化，以考虑具有大 Q 因子的 FRR 的特性（ $2\乘以 10^{9}$ ) 但自由光谱范围相对较小 (2 MHz)。稳定激光器的测量性能表明，在 1 kHz 至 10 kHz 范围内，频率噪声水平低至 0.4 Hz ² /Hz，线宽低于 30 Hz，积分时间为 5 ms。