Characterization of a 30 GHz Spaced Astro-Comb Filtered by a Fabry–Pérot Cavity in Vacuum

作者：Qi Zhou, Ruoao Yang, Fei Zhao, Gang Zhao, Aimin Wang, Xing Chen, Zhigang Zhang · 发表于：Photonics · 年份：2025 · DOI：10.3390/photonics12121184 · 被引用次数：2 · 研究领域：Advanced Fiber Laser Technologies、Advanced Frequency and Time Standards、Semiconductor Lasers and Optical Devices

We demonstrate a compact astro-comb with ~30 GHz line spacing covering the 560–900 nm range, seeded by a 1 GHz Yb:fiber laser frequency comb phase-locked to a rubidium clock for long-term frequency stability. The comb spacing is multiplied by a passively stabilized Fabry–Pérot cavity, which is vacuum-sealed (3.3 × 10−5 Pa) and temperature-controlled at 25 ± 0.05 °C, exhibiting a resonance linewidth of 80.56 MHz. Characterization using a high-resolution Fourier-transform spectrometer reveals sharp, evenly spaced comb lines with a maximum side-mode suppression ratio of 23.86 dB. The estimated radial velocity (RV) precision reaches ~63 cm/s, and further reduction in measurement noise is expected to achieve <10 cm/s precision, meeting the stringent requirements of next-generation astronomical spectrographs.