Faculty of Electronics, Photonics and Microsystem, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland.
Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
Sensors (Basel). 2022 Jul 23;22(15):5504. doi: 10.3390/s22155504.
In this paper, the combination of using an anti-resonant hollow-core fiber (ARHCF), working as a gas absorption cell, and an inexpensive, commercially available watch quartz tuning fork (QTF), acting as a detector in the quartz-enhanced photothermal spectroscopy (QEPTS) sensor configuration is demonstrated. The proof-of-concept experiment involved the detection of methane (CH) at 1651 nm (6057 cm). The advantage of the high QTF Q-factor combined with a specially designed low-noise amplifier and additional wavelength modulation spectroscopy with the second harmonic (2f-WMS) method of signal analysis, resulted in achieving a normalized noise-equivalent absorption (NNEA) at the level of 1.34 × 10 and 2.04 × 10 W cm Hz for 1 and 100 s of integration time, respectively. Results obtained in that relatively non-complex sensor setup show great potential for further development of cost-optimized and miniaturized gas detectors, taking advantage of the combination of ARHCF-based absorption cells and QTF-aided spectroscopic signal retrieval methods.
本文展示了一种将反共振空芯光纤（ARHCF）用作气体吸收池，并结合廉价、市售的手表石英音叉（QTF）作为石英增强光热光谱（QEPTS）传感器配置中的探测器的组合。概念验证实验涉及在 1651nm（6057cm）处检测甲烷（CH）。高 QTF Q 因子与专门设计的低噪声放大器以及附加的二次谐波（2f-WMS）信号分析方法相结合的优势，使得在 1 和 100 秒的积分时间内，分别实现了归一化噪声等效吸收（NNEA）水平为 1.34×10和 2.04×10WcmHz。在相对非复杂的传感器设置中获得的结果表明，利用基于 ARHCF 的吸收池和 QTF 辅助光谱信号检索方法的组合，进一步开发具有成本效益和小型化的气体探测器具有很大的潜力。
