The large volume and weak environmental adaptability of fiber optical frequency combs (OFCs) have become the main obstacles for their applications in various fields. To address these issues, in this study, we present a compact, low-cost f-to-2f interferometer and fiber actuator with a large tuning range and a high control bandwidth for a 200-MHz OFC that is based on a 1.5-μm all-polarization-maintaining fiber mode-locked laser. By employing customized fiber-coupled gradient index lenses, our f-to-2f interferometer is encapsulated in a miniature tube with a diameter of only 4 mm and a length of 40 mm, which substantially reduces the optical section size of the frequency comb as compared to conventional devices. The carrier envelope offset beat with a signal-to-noise ratio of 40 dB is detected in a resolution bandwidth of 360 kHz. In addition, a laboratory-made piezoelectric transducer-driven mechanical actuator for repetition rate regulation exhibited a large tuning range of 106 kHz (corresponding to an effective temperature drift of 53 °C) and a high control bandwidth of approximately 1 kHz. This resulted in a robust repetition rate locking with an Allan deviation of 330 μHz at a gate time of 1 s and a residual integrated timing jitter of 418 fs [3 Hz to 1 MHz] when referenced to a hydrogen maser. Along with reducing the size and improving the environmental adaptability of the OFC, our design can also decrease the power consumption of the system significantly. Our findings provide a new direction to the development of OFCs for various applications.

中文翻译：

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紧凑型、高性能全偏振保持 Er：光纤频率梳，带单光纤驱动器

光纤频率梳（OFCs）体积大、环境适应性差，已成为其在各个领域应用的主要障碍。为了解决这些问题，在本研究中，我们提出了一种紧凑、低成本的 f-to-2f 干涉仪和光纤致动器，具有大调谐范围和高控制带宽，用于基于 1.5-μm 的 200-MHz OFC全保偏光纤锁模激光器。通过采用定制的光纤耦合梯度折射率透镜，我们的 f-2f 干涉仪封装在一个直径仅为 4 mm、长度仅为 40 mm 的微型管中，相比之下，这大大减小了频率梳的光学截面尺寸到传统设备。在 360 kHz 的分辨率带宽内检测到信噪比为 40 dB 的载波包络偏移差拍。此外，用于重复率调节的实验室制造的压电换能器驱动的机械致动器具有 106 kHz 的大调谐范围（对应于 53 °C 的有效温度漂移）和大约 1 kHz 的高控制带宽。这导致了稳健的重复率锁定，在 1 s 的选通时间下具有 330 μHz 的艾伦偏差和 418 fs [3 Hz 至 1 MHz] 的残余集成定时抖动，当参考氢脉泽时。在减小OFC的尺寸和提高环境适应性的同时，我们的设计还可以显着降低系统的功耗。我们的发现为开发各种应用的 OFC 提供了新的方向。