Fulltext

CO2 isotope sensor using a broadband infrared source, a spectrally narrow 4.4 μm quantum cascade detector, and a Fourier spectrometer

Hofstetter, D. ; Di Francesco, J. ; Hvozdara, L. ; Herzig, H.-P ; Beck, M.

In: Applied Physics B, 2011, vol. 103, no. 4, p. 967-970

Add to personal list
    Title
    • CO2 isotope sensor using a broadband infrared source, a spectrally narrow 4.4 μm quantum cascade detector, and a Fourier spectrometer
    Author
    • Hofstetter, D.. Institute of Physics, University of Neuchâtel, 51 Avenue de Bellevaux, 2009, Neuchâtel, Switzerland
    • Di Francesco, J.. Institute of Physics, University of Neuchâtel, 51 Avenue de Bellevaux, 2009, Neuchâtel, Switzerland
    • Hvozdara, L.. Optics and Photonics Technology Laboratory, Institute of Microtechnology, EPFL, A.-L. Breguet 2, 2000, Neuchâtel, Switzerland
    • Herzig, H.-P. Optics and Photonics Technology Laboratory, Institute of Microtechnology, EPFL, A.-L. Breguet 2, 2000, Neuchâtel, Switzerland
    • Beck, M.. Quantum Optoelectronics Group, Institute of Quantum Electronics, ETHZ, Wolfgang-Pauli-Strasse 16, 8093, Zurich, Switzerland
    Document Type
    • Postprint
    Classification
    • Physics
    OAI-PMH Identifier
    • oai:doc.rero.ch:310550
    Summary
    We report a prototype CO2 gas sensor based on a simple blackbody infrared source and a spectrally narrow quantum cascade detector (QCD). The detector absorption spectrum is centered at 2260cm−1 (4.4μm) and has a full width at half maximum of 200cm−1 (25meV). It covers strong absorption bands of two spectrally overlapping CO2 isotopomers, namely the P-branch of 12CO2 and the R-branch of 13CO2. Acquisition of the spectral information and data treatment were performed in a Fourier transform infrared (FTIR) spectrometer. By flushing its sample compartment either with nitrogen, dry fresh air, ambient air, or human breath, we were able to determine CO2 concentrations corresponding to the different gas mixtures. Adetection limit of 500ppb was obtained in these experiments