This paper reports a mini-resonant photoacoustic sensor for high-sensitivity trace gas sensing. The sensor primarily contains a sphere-cylinder coupled acoustic resonator, a cylindrical buffer chamber, and a fiber-optic acoustic sensor. The acoustic field distributions of this mini-resonant photoacoustic sensor and the conventional T-type resonant photoacoustic sensor have been carefully evaluated, showing that the first-order resonance frequency of the present mini-resonant photoacoustic sensor is reduced by nearly a half compared to that of the T-type resonant photoacoustic sensor. The volume of the developed photoacoustic cavity is only about 0.8 cm. Trace methane is selected as the target analytical gas and a detection limit of 101 parts-per-billion at 100-s integration time has been achieved, corresponding to a normalized noise equivalent absorption (NNEA) coefficient of 1.04 × 10 W·cm·Hz. The developed mini-resonant photoacoustic sensor provides potential for high-sensitivity trace gas sensing in narrow spaces.

中文翻译：

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基于球柱耦合声谐振器的微型谐振光声传感器，用于高灵敏度痕量气体传感

本文报道了一种用于高灵敏度痕量气体传感的微型谐振光声传感器。该传感器主要包含球柱耦合声学谐振器、圆柱形缓冲室和光纤声学传感器。对该微型谐振光声传感器和传统T型谐振光声传感器的声场分布进行了仔细评估，结果表明，该微型谐振光声传感器的一阶谐振频率比传统T型谐振光声传感器降低了近一半。 T型谐振光声传感器。所开发的光声腔体积仅为0.8 cm左右。选择痕量甲烷作为目标分析气体，在100秒积分时间内实现了十亿分之101的检测限，对应于归一化噪声等效吸收（NNEA）系数为1.04×10 W·cm·Hz 。开发的微型谐振光声传感器为狭窄空间内的高灵敏度痕量气体传感提供了潜力。