Chen Weipeng, Qiao Shunda, He Ying, Zhu Jie, Wang Kang, Qi Lei, Zhou Sheng, Xiao Limin, Ma Yufei
National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150001, China.
Zhengzhou Research Institute, Harbin Institute of Technology, Zhengzhou 450000, China.
Photoacoustics. 2024 Feb 9;36:100594. doi: 10.1016/j.pacs.2024.100594. eCollection 2024 Apr.
In this article, a mid-infrared all-fiber light-induced thermoelastic spectroscopy (LITES) sensor based on a hollow-core anti-resonant fiber (HC-ARF) was reported for the first time. The HC-ARF was applied as a light transmission medium and gas chamber. The constructed all-fiber structure has merits of low loss, easy optical alignment, good system stability, reduced sensor size and cost. The mid-infrared transmission structure can be utilized to target the strongest gas absorption lines. The reversely-tapered SM1950 fiber and the HC-ARF were spatially butt-coupled with a V-shaped groove between the two fibers to facilitate gas entry. Carbon monoxide (CO) with an absorption line at 4291.50 cm (2.33 µm) was chosen as the target gas to verify the sensing performance. The experimental results showed that the all-fiber LITES sensor based on HC-ARF had an excellent linear response to CO concentration. Allan deviation analysis indicated that the system had excellent long-term stability. A minimum detection limit (MDL) of 3.85 ppm can be obtained when the average time was 100 s.
本文首次报道了一种基于空芯反谐振光纤（HC-ARF）的中红外全光纤光热弹性光谱（LITES）传感器。该HC-ARF被用作光传输介质和气室。所构建的全光纤结构具有低损耗、易于光学对准、系统稳定性好、传感器尺寸和成本降低等优点。中红外传输结构可用于瞄准最强的气体吸收线。将反向锥形SM1950光纤与HC-ARF在两根光纤之间通过V形槽进行空间对接耦合，以利于气体进入。选择在4291.50 cm（2.33 µm）处有吸收线的一氧化碳（CO）作为目标气体来验证传感性能。实验结果表明，基于HC-ARF的全光纤LITES传感器对CO浓度具有出色的线性响应。阿伦偏差分析表明该系统具有出色的长期稳定性。当平均时间为100 s时，可获得3.85 ppm的最低检测限。
