Fiber-amplifier-enhanced QEPAS sensor for simultaneous trace gas detection of NH₃ and H₂S.
A selective and sensitive quartz enhanced photoacoustic spectroscopy (QEPAS) sensor, employing an erbium-doped fiber amplifier (EDFA), and a distributed feedback (DFB) laser operating at 1582 nm was demonstrated for simultaneous detection of ammonia (NH₃) and hydrogen sulfide (H₂S). Two interference-free absorption lines located at 6322.45 cm(-1) and 6328.88 cm(-1) for NH₃ and H₂S detection, respectively, were identified. The sensor was optimized in terms of current modulation depth for both of the two target gases. An electrical modulation cancellation unit was equipped to suppress the background noise caused by the stray light. An Allan-Werle variance analysis was performed to investigate the long-term performance of the fiber-amplifier-enhanced QEPAS sensor. Benefitting from the high power boosted by the EDFA, a detection sensitivity (1σ) of 52 parts per billion by volume (ppbv) and 17 ppbv for NH₃ and H₂S, respectively, were achieved with a 132 s data acquisition time at atmospheric pressure and room temperature.
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. beijing2008whp@163.com.
Hongpeng
H
Wu
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. donglei@sxu.edu.cn.
Lei
L
Dong
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. liuxiaoli@163.com.
Xiaoli
X
Liu
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. zhenghuadan@126.com.
Huadan
H
Zheng
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. yinxukun@163.com.
Xukun
X
Yin
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. mwg@sxu.edu.cn.
Weiguang
W
Ma
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. k1226@sxu.edu.cn.
Lei
L
Zhang
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. ywb65@sxu.edu.cn.
Wangbao
W
Yin
State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China. tjia@sxu.edu.cn.
Suotang
S
Jia
D000641:Ammonia / Q000032:analysis*; D004784:Environmental Monitoring; D004867:Equipment Design; D004871:Erbium; D006862:Hydrogen Sulfide / Q000032:analysis*; D061088:Photoacoustic Techniques / Q000295:instrumentation / Q000379:methods*; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods*
D000641:Ammonia; D004871:Erbium; D006862:Hydrogen Sulfide
erbium doped fiber amplifier; modulation cancelation method; multi-component traces gas detection; near-infrared distributed feedback laser; quartz enhanced photoacoustic spectroscopy