Abstract

Spectroscopic gas sensing technologies based on absorption and Raman scattering are fast, nondestructive, long-term stable and highly selective. By making use of an optically resonant cavity, the sensitivity can be enhanced hundreds to thousands of times. However, frequency-locking technology is necessary to maintain a stable resonant condition. In this review, various applications of Pound-Drever-Hall (PDH) and optical feedback (OF) frequency-locking cavity-enhanced spectroscopy (cavity ring-down spectroscopy, cavity-enhanced absorption spectroscopy and cavity-enhanced Raman spectroscopy) for highly sensitive gas sensing are presented. The effect of frequency-locking cavity-enhanced spectroscopy for improving the sensitivity of gas sensing is demonstrated. In addition, the key parameters and advantages as well as limitations of different frequency-locking cavity-enhanced spectroscopy are summarized and discussed.

摘要

基于吸收和拉曼散射的光谱气体传感技术具有快速、无损、长期稳定和高选择性。通过利用光学谐振腔，灵敏度可以提高数百到数千倍。然而，锁频技术对于维持稳定的谐振条件是必要的。在这篇综述中，Pound-Drever-Hall (PDH) 和光反馈 (OF) 锁频腔增强光谱（腔衰荡光谱、腔增强吸收光谱和腔增强拉曼光谱）在高灵敏度方面的各种应用介绍了气体传感。证明了锁频腔增强光谱对提高气体传感灵敏度的作用。此外，