Doppler-broadened fiber-laser-based NICE-OHMS: improved detectability
2007 (English)In: Optics Express, ISSN 1094-4087, Vol. 15, no 17, 10822-10831 p.Article in journal (Refereed) Published
The performance of fiber-laser-based noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) has been improved by elimination of the technical constraints that limited its first demonstration. Doppler-broadened detection of C2H2 and CO2 at ~1531 nm is demonstrated using a cavity with a finesse of 4800. Frequency and wavelength modulated detection at absorption and dispersion phase are compared and the optimum mode of detection is discussed. A minimum detectable absorption of 8 × 10-11 cm-1, which corresponds to a detection limit of 4.5 ppt (2 ppt·m) for C2H2, was obtained for an acquisition time of 0.7 s by lineshape fitting. The linearity of the pressure dependence of the signal strengths is investigated for both C2H2 and CO2.
Place, publisher, year, edition, pages
2007. Vol. 15, no 17, 10822-10831 p.
IdentifiersURN: urn:nbn:se:umu:diva-2704DOI: 10.1364/OE.15.010822ISI: 000249336000039PubMedID: 19547439OAI: oai:DiVA.org:umu-2704DiVA: diva2:140951