中国物理B ›› 2023, Vol. 32 ›› Issue (10): 104209-104209.doi: 10.1088/1674-1056/acdac1
Yi-Xuan Liu(刘艺璇), Zhou-Bing Wang(王周兵), Xin-Xin Wei(韦欣欣), Jing-Jing Wang(王静静)†, Xin Meng(孟鑫), and Gui-Lin Mao(毛桂林)‡
Yi-Xuan Liu(刘艺璇), Zhou-Bing Wang(王周兵), Xin-Xin Wei(韦欣欣), Jing-Jing Wang(王静静)†, Xin Meng(孟鑫), and Gui-Lin Mao(毛桂林)‡
摘要: This study established a novel method for the simultaneous detection of two-component gases. Radio frequency (RF) white noise disturbance laser current and wavelength modulation were simultaneously used to improve the off-axis integrated cavity output spectroscopy technique, and a high-precision dual modulation OA-ICOS (RF-WM-OA-ICOS) system was established. The two laser beams were coupled into one laser beam that was applied incident to the cavity of RF-WM-OA-ICOS system. The second harmonic signals of CH$_{4}$ and CO$_{2}$ gas simultaneously appeared in the rising or falling edge of a triangular wave. This method was used to measure CH$_{4}$ and CO$_{2}$ with different concentrations. The results indicated that the proposed system has high stability and can accurately and simultaneously measure the concentrations of CH$_{4}$ and CO$_{2}$, with an optimal integration time of 220 s. The minimum detection limit was 10 ppb for CH$_{4}$ and 1.5 ppm for CO$_{2}$. The corresponding noise equivalent absorption sensitivity values were calculated as $2.67 \times 10^{-13}$ cm$^{-1}\cdot$Hz$^{-1/2}$ and $5.18 \times 10^{-11}$ cm$^{-1}\cdot$Hz$^{-1/2}$, respectively. The proposed dual-component gas simultaneous detection method can also be used for high-precision simultaneous detection of other gases. Therefore, this study may serve as a reference for developing portable multicomponent gas analyzers.
中图分类号: (Spectral absorption by atmospheric gases)