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arXiv · 1801.06530

In-water chemical sensing by fiber-optic evanescent waves spectroscopy using mid-infrared quantum cascade lasers

Paul Chevalier·Marco Piccardo·Guy-Mael de Naurois·Ilan Gabay·Abraham Katzir·Federico Capasso
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Abstract

The ability of detecting harmful chemicals is an important safety requirement for drinking water systems. An apparatus for in-water chemical sensing based on the absorption of evanescent waves generated by a quantum cascade laser array propagating in a silver halide optical fiber immersed into water is demonstrated. We present a theoretical analysis of the sensitivity of the system and experimentally characterize its real-time response and spectroscopic detection for injection of a sample chemical (ethanol) in a tube containing water.

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Paul Chevalier, Marco Piccardo, Guy-Mael de Naurois, Ilan Gabay, Abraham Katzir, Federico Capasso. 2017-12-08. In-water chemical sensing by fiber-optic evanescent waves spectroscopy using mid-infrared quantum cascade lasers. https://doi.org/10.1016/j.snb.2018.01.159

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