Mid-infrared all-fiber light-induced thermoelastic spectroscopy sensor based on hollow-core anti-resonant fiber

Weipeng Chen; Shunda Qiao; Ying He; Jie Zhu; Kang Wang; Lei Qi; Sheng Zhou; Limin Xiao; Yufei Ma

doi:10.1016/j.pacs.2024.100594

Mid-infrared all-fiber light-induced thermoelastic spectroscopy sensor based on hollow-core anti-resonant fiber

Photoacoustics. 2024 Feb 9:36:100594. doi: 10.1016/j.pacs.2024.100594. eCollection 2024 Apr.

Authors

Weipeng Chen^{1

2}, Shunda Qiao^{1

2}, Ying He^{1

2}, Jie Zhu³, Kang Wang³, Lei Qi⁴, Sheng Zhou⁵, Limin Xiao³, Yufei Ma^{1

2}

Affiliations

¹ National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150001, China.
² Zhengzhou Research Institute, Harbin Institute of Technology, Zhengzhou 450000, China.
³ Advanced Fiber Devices and Systems Group, Key Laboratory of Micro and Nano Photonic Structures (MoE), Key Laboratory for Information Science of Electromagnetic Waves (MoE), Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, School of Information Science and Technology, Fudan University, Shanghai, China.
⁴ Beijing Institute of Spacecraft Environment Engineering, Beijing 100094, China.
⁵ Laser Spectroscopy and Sensing Laboratory, Anhui University, Hefei 230601, China.

Abstract

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^-1 (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.

Keywords: All-fiber; Hollow-core anti-resonant fiber; Light-induced thermoelastic spectroscopy; Mid-infrared.