Mid-IR optical sensor for CO2 detection based on fluorescence absorbance of Dy3+:Ga5Ge20Sb10S65 fibers

Florent Starecki (1, 2) , Fréderic Charpentier (3) , Jean-Louis Doualan (2) , Lionel Quetel (4) , Karine Michel (5) , Radwan Chahal (1) , Johann Troles (1) , Bruno Bureau (1) , Alain Braud (2) , Patrice Camy (2) , Virginie Moizan (1) , Virginie Nazabal (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 CIMAP - UMR 6252 - Centre de recherche sur les Ions, les MAtériaux et la Photonique
3 I2M - Institut de Mécanique et d'Ingénierie de Bordeaux
4 IDIL Fibres Optiques
5 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)

The Dy3+ doped Ga5Ge20Sb10S65 bulk glass provides good emission efficiency in the middle IR with a better brightness than the blackbody sources. Sulfide single index fibers doped with Dy3+ (500-​3000 ppm) were drawn with optical attenuation of about 1-​3 dB​/m, suitable to develop fluorescence sources for chem. anal. by optical absorption in middle IR. They particularly present a broad emission around 4-​5 μm, making them attractive for CO2 detection. Considering the low cost and efficient Dy3+ pumping scheme by means of a com. laser diode, the Dy3+ sulfide fiber reveals potential for developing a CO2 optical sensor. Using the 4.35 μm broad emission of a Dy3+ doped Ga5Ge20Sb10S65 fiber combined with a differential measurement technique, the CO2 gas concn. measurement was carried out fruitfully. For this specific application, the CO2 detection threshold was fixed at about 400 ppm corresponding to atm. concn. and was successfully reached for a cell length of 1.5 cm with a resoln. of about 5​%. The sensitivity of the setup is mainly related to the size of the cell, deliberately reduced to develop a robust and compact system for natural geol. sites.

Mots clés: Chalcogenide fibers; Chalcogenide glass; CO2 detection; Rare earth; Dysprosium; Mid-IR optical sensor

Domaines: Matériaux

Florent Starecki, Fréderic Charpentier, Jean-Louis Doualan, Lionel Quetel, Karine Michel, et al.. Mid-IR optical sensor for CO2 detection based on fluorescence absorbance of Dy3+:Ga5Ge20Sb10S65 fibers. Sensors and Actuators A: Physical , 2015, 207 (PartA), pp.518-525. ⟨10.1016/j.snb.2014.10.011⟩. ⟨hal-01077740⟩