Investigation of A Slow-Light Enhanced Near-Infrared Absorption Spectroscopic Gas Sensor, Based on Hollow-Core Photonic Band-Gap Fiber

• Main Authors: Zhi-Fa Wu, Chuan-Tao Zheng, Zhi-Wei Liu, Dan Yao, Wen-Xue Zheng, Yi-Ding Wang, Fei Wang, Da-Ming Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2018-07-01
• Series: Sensors
• Subjects: photonic band-gap fiber; infrared absorption spectroscopy; gas sensor; slow light
• Online Access: http://www.mdpi.com/1424-8220/18/7/2192
• ISSN: 1424-8220

Generic modeling and analysis of a slow-light enhanced absorption spectroscopic gas sensor was proposed, using a mode-tuned, hollow-core, photonic band-gap fiber (HC-PBF) as an absorption gas cell. Mode characteristics of the un-infiltrated and infiltrated HC-PBF and gas absorption enhancement of the infiltrated HC-PBF were analyzed. A general rule of microfluidic parameters for targeting different gas species in the near-infrared was obtained. Ammonia (NH3) was used as an example to explore the effects of slow light on gas detection. The second harmonic (2f) signal and Allan deviation were theoretically investigated based on the derived formulations.