Authors: A Vicet B Cousin M Jahjah Y El Kaim Y Rouillard B Jaillard
Publish Date: 2011/04/19
Volume: 104, Issue: 1, Pages: 199-206
Abstract
We present a study of a sensor probe based on tunable diode laser absorption spectroscopy using antimonidebased diode lasers emitting at 23 and 26 μm The lasers were fabricated by molecular beam epitaxy in the IES laboratory The active regions are based on InGaAsSb/AlGaAsSb quantum wells grown on a GaSbN substrate The diode lasers operate at room temperature in a continuous wave CW regime and exhibit 5 mW of emitted powerA linear optical setup using the two emitting facets of the diode lasers was developed By using a second derivative detection by wavelength modulation spectroscopy we obtained a CH4 detection limit of 9 ppm m The sensor is designed to be used in soil and to measure CH4 CO2 and H2O which are important constituents of the soil atmosphere generated by anaerobic digestion microbial respiration or water transfer
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