Gong Zhenfeng, Wu Guojie, Jiang Xu, Li Haie, Gao Tianli, Guo Min, Ma Fengxiang, Chen Ke, Mei Liang, Peng Wei, Yu Qingxu
Opt Express. 2021 Apr 26;29(9):13600-13609. doi: 10.1364/OE.424387.
This paper presents an all-optical high-sensitivity resonant photoacoustic (PA) sensor to realize remote, long-distance and space-limited trace gas detection. The sensor is an integration of a T-type resonant PA cell and a particular cantilever-based fiber-optic acoustic sensor. The finite element simulations about the cantilever vibration mode and the PA field distributions are carried out based on COMSOL. The all-optical high-sensitivity resonant PA sensor, together with a high-speed spectrometer and a DFB laser source, makes up of a photoacoustic spectroscopy (PAS) system which is employed for CH detection. The measured sensitivity is 0.6 pm/ppm in the case of 1000 s average time, and the minimum detection limit (MDL) reaches 15.9 parts per billion (ppb). The detective light source and the excitation light source are all transmitted by optical fibers, therefore remote and long-distance measurement of trace gas can be realized. Furthermore, the excitation light source and the acoustic sensor are designed at the same side of the PA cell, the sensor may be used for space-limited trace gas detection.
本文提出了一种全光高灵敏度共振光声（PA）传感器，以实现远程、长距离和空间受限的痕量气体检测。该传感器是T型共振PA池与特定的基于悬臂的光纤声学传感器的集成。基于COMSOL对悬臂振动模式和PA场分布进行了有限元模拟。全光高灵敏度共振PA传感器与高速光谱仪和分布式反馈（DFB）激光源一起构成了用于CH检测的光声光谱（PAS）系统。在平均时间为1000 s的情况下，测量灵敏度为0.6 pm/ppm，最低检测限（MDL）达到15.9十亿分之一（ppb）。探测光源和激发光源均通过光纤传输，因此可以实现痕量气体的远程和长距离测量。此外，激发光源和声传感器设计在PA池的同一侧，该传感器可用于空间受限的痕量气体检测。
