TY - JOUR
T1 - ICL-Based OF-CEAS
T2 - A Sensitive Tool for Analytical Chemistry
AU - Manfred, Katherine M.
AU - Hunter, Katharine M.
AU - Ciaffoni, Luca
AU - Ritchie, Grant A.D.
PY - 2017/1/3
Y1 - 2017/1/3
N2 - Optical-feedback cavity-enhanced absorption spectroscopy (OF-CEAS) using mid-infrared interband cascade lasers (ICLs) is a sensitive technique for trace gas sensing. The setup of a V-shaped optical cavity operating with a 3.29 μm cw ICL is detailed, and a quantitative characterization of the injection efficiency, locking stability, mode matching, and detection sensitivity is presented. The experimental data are supported by a model to show how optical feedback affects the laser frequency as it is scanned across several longitudinal modes of the optical cavity. The model predicts that feedback enhancement effects under strongly absorbing conditions can cause underestimations in the measured absorption, and these predictions are verified experimentally. The technique is then used in application to the detection of nitrous oxide as an exemplar of the utility of this technique for analytical gas phase spectroscopy. The analytical performance of the spectrometer, expressed as noise equivalent absorption coefficient, was estimated as 4.9 × 10-9 cm -1 Hz-1/2, which compares well with recently reported values.
AB - Optical-feedback cavity-enhanced absorption spectroscopy (OF-CEAS) using mid-infrared interband cascade lasers (ICLs) is a sensitive technique for trace gas sensing. The setup of a V-shaped optical cavity operating with a 3.29 μm cw ICL is detailed, and a quantitative characterization of the injection efficiency, locking stability, mode matching, and detection sensitivity is presented. The experimental data are supported by a model to show how optical feedback affects the laser frequency as it is scanned across several longitudinal modes of the optical cavity. The model predicts that feedback enhancement effects under strongly absorbing conditions can cause underestimations in the measured absorption, and these predictions are verified experimentally. The technique is then used in application to the detection of nitrous oxide as an exemplar of the utility of this technique for analytical gas phase spectroscopy. The analytical performance of the spectrometer, expressed as noise equivalent absorption coefficient, was estimated as 4.9 × 10-9 cm -1 Hz-1/2, which compares well with recently reported values.
UR - http://www.scopus.com/inward/record.url?scp=85019425042&partnerID=8YFLogxK
U2 - 10.1021/acs.analchem.6b04030
DO - 10.1021/acs.analchem.6b04030
M3 - Article
AN - SCOPUS:85019425042
SN - 0003-2700
VL - 89
SP - 902
EP - 909
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 1
ER -
