In this work, we present for the first time a laser-based dual gas sensor utilizing a silica-based Antiresonant Hollow-Core Fiber (ARHCF) operating in the Near- and Mid-Infrared spectral region. A 1-m-long fiber with an 84-µm diameter air-core was implemented as a low-volume absorption cell in a sensor configuration utilizing the simple and well-known Wavelength Modulation Spectroscopy (WMS) method. The fiber was filled with a mixture of methane (CH₄) and carbon dioxide (CO₂), and a simultaneous detection of both gases was demonstrated targeting their transitions at 3.334 µm and 1.574 µm, respectively. Due to excellent guidance properties of the fiber and low background noise, the proposed sensor reached a detection limit down to 24 parts-per-billion by volume for CH₄ and 144 parts-per-million by volume for CO₂. The obtained results confirm the suitability of ARHCF for efficient use in gas sensing applications for over a broad spectral range. Thanks to the demonstrated low loss, such fibers with lengths of over one meter can be used for increasing the laser-gas molecules interaction path, substituting bulk optics-based multipass cells, while delivering required flexibility, compactness, reliability and enhancement in the sensor’s sensitivity.

中文翻译：

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基于反谐振空心核光纤的双气体传感器，用于检测近红外和中红外区域中的甲烷和二氧化碳。

在这项工作中，我们首次展示了一种基于激光的双气体传感器，该传感器采用了在近红外和中红外光谱区域中工作的基于二氧化硅的反谐振空心纤芯（ARHCF）。利用简单且众所周知的波长调制光谱（WMS）方法，将直径为84 µm的1 m长光纤作为传感器配置中的小体积吸收池。光纤中充满了甲烷（CH ₄）和二氧化碳（CO ₂）的混合物，同时检测到两种气体的过渡分别在3.334 µm和1.574 µm。由于出色的光纤导引性能和低背景噪音，拟议的传感器对CH ₄的检测限达到了低至百万分之24的体积CO ₂的体积比为百万分之144 。获得的结果证实了ARHCF适用于在广泛的光谱范围内有效地用于气体传感应用。由于证明了低损耗，这种长度超过一米的光纤可用于增加激光-气体分子的相互作用路径，取代基于体光学的多通道电池，同时提供所需的灵活性，紧凑性，可靠性和传感器灵敏度的增强。