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arXiv · 2407.20201

Methane Sensing via Unbalanced Nonlinear Interferometry using a CMOS Camera

Jinghan Dong·Arthur C. Cardoso·Haichen Zhou·Jingrui Zhang·Weijie Nie·Alex S. Clark·John G. Rarity
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Abstract

Here we present a high-sensitivity, rapid, and low-cost method for methane sensing based on a nonlinear interferometer. This method utilizes signal photons generated by stimulated parametric down-conversion (ST-PDC), enabling the use of a silicon detector to capture high-precision methane absorption spectra in the mid-infrared region. By controlling the system loss, we achieve more significant changes in visibility, thereby increasing sensitivity. The methane concentration within a gas cell is determined accurately. In addition, ST-PDC enables long-distance sensing and the capability to measure low ambient methane concentrations in the real world. A low-cost CMOS camera is employed to capture spatial interference fringes, ensuring fast and efficient detection.

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Jinghan Dong, Arthur C. Cardoso, Haichen Zhou, Jingrui Zhang, Weijie Nie, Alex S. Clark, John G. Rarity. 2024-07-29. Methane Sensing via Unbalanced Nonlinear Interferometry using a CMOS Camera. https://arxiv.org/abs/2407.20201

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