We propose a novel high‐performance dual‐resonance enhanced photoacoustic spectroscopy (DRE‐PAS) gas sensor based on a highly sensitive fiber optic cantilever beam microphone and a high‐Q spherical photoacoustic cell (PAC). The first‐order resonant frequency (FORF) of the spherical PAC is analyzed by finite element analysis to match the FORF of the cantilever microphone for the double resonance enhancement of the photoacoustic signal. The photoacoustic spectroscopy (PAS) system, including the DRE‐PAS sensor, a 1532.8 nm distributed feedback laser, and a high‐speed spectrometer, has been successfully exploited for trace acetylene (C2H2) detection. The experimental results show that the limit of detection (LOD) is 106.8 parts‐per‐billion (ppb) with an integral time of 1 s, and the LOD can be further reduced to 11.03 ppb by Allan‐Werle deviation for 100 s integral time. The normalized noise equivalent absorption coefficient can be obtained as 2.44 × 10−8 cm−1 WHz−1/2. The reported DRE‐PAS gas sensor has the superior characteristics of photoacoustic signal enhancement, high sensitivity, and strong antielectromagnetic interference capability, which can provide a new solution for PAS development.

中文翻译：

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基于光纤悬臂梁麦克风和球形光声池的双共振增强光声光谱气体传感器


我们提出了一种基于高灵敏度光纤悬臂梁麦克风和高 Q 球形光声池（PAC）的新型高性能双共振增强光声光谱（DRE-PAS）气体传感器。通过有限元分析，对球形PAC的一阶谐振频率（FORF）进行分析，以匹配悬臂麦克风的FORF，实现光声信号的双谐振增强。光声光谱 (PAS) 系统，包括 DRE-PAS 传感器、1532.8 nm 分布式反馈激光器和高速光谱仪，已成功用于痕量乙炔 (C2H2) 检测。实验结果表明，积分时间为1 s时，检测限(LOD)为106.8 ppb，积分时间为100 s时，通过Allan-Werle偏差，LOD可进一步降低至11.03 ppb 。可以得到归一化噪声等效吸收系数为2.44×10−8 cm−1 WHZ−1/2。报道的DRE-PAS气体传感器具有光声信号增强、灵敏度高、抗电磁干扰能力强等优越特性，可为PAS的发展提供新的解决方案。