Open-path cavity ring-down spectroscopy sensor for atmospheric ammonia

  title={Open-path cavity ring-down spectroscopy sensor for atmospheric ammonia},
  author={Soran Shadman and Charles Rose and Azer P. Yalin},
  journal={Applied Physics B},
An open-path cavity ring-down spectroscopy (CRDS) sensor has been developed for measurement of atmospheric ammonia (NH3) and represents the first use of open-path CRDS in the mid-infrared region. The sensor uses a continuous-wave distributed feedback quantum cascade laser at 10.33 μm to target strong absorption features. The optical cavity is constructed with two high-reflectivity mirrors (R = 0.9995). The open-path configuration removes inlet effects, which are very challenging for closed-path… 
8 Citations
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