A continuous wave quantum cascade laser (QCL), operating near 8.1 μm, was used for wavelength modulation spectroscopy of methane (CH4) and nitrous oxide (N2O) stable isotopes. Several rotational transitions of 14N216O, 15N14N16O, 14N218O, 14N217O, 13CH4 and 12CH4 fundamental bands were detected. The noise-equivalent absorbance was measured to be less than 10-5 in a 1-Hz bandwidth. A characterization of the laser source was also performed. The use of a QCL spectrometer for high-precision isotope ratio measurements is discussed.
|Original language||English (US)|
|Number of pages||5|
|Journal||European Physical Journal D|
|State||Published - Jun 2002|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics