We demonstrate an actively stabilized cavity-enhanced dual-comb spectroscopy to improve comb transmission through a high-finesse optical cavity. In this dual-comb spectroscopic method, one comb is phase-locked to a 34 cm cavity with a finesse of about 15 700, which is stabilized to the molecular absorption line. With this actively stabilized scheme, all comb lines can be locked to the center of the corresponding cavity mode. Comparison experiments are conducted to demonstrate the necessity of the proposed actively stabilized scheme for robust comb-cavity coupling under external disturbances. We achieved a signal-to-noise ratio of 114.5 with an averaging time of 9 ms for a spectral range of 4.5 cm−1, contributing to the intensity absorption coefficient of 5.14 × 10−8 cm−1 and the noise-equivalent absorption per spectral element of 3.08 × 10−10 cm−1Hz−1/2.

中文翻译：

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通过分子吸收线锁定稳定的腔体增强双梳光谱


我们展示了一种主动稳定腔增强双光梳光谱，以改善通过高精度光腔的光梳透射。在这种双梳光谱方法中，一个梳子锁相到 34 cm 的腔体上，其精细度约为 15 700，该腔体稳定在分子吸收线上。通过这种主动稳定的方案，所有梳状线都可以锁定到相应腔模式的中心。进行了比较实验，以证明所提出的主动稳定方案在外部干扰下实现鲁棒梳状腔耦合的必要性。在 4.5 cm-1 的光谱范围内，我们实现了 114.5 的信噪比，平均时间为 9 ms，有助于 5.14 × 10-8 cm-1 的强度吸收系数和每个光谱元件的噪声等效吸收为 3.08 × 10-10 cm-1Hz-1/2。