Doppler-broadened fiber-laser-based NICE-OHMS - Improved detectability
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 C(2)H(2) and CO(2) at ~1531 nm is demonstrated us...
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Published in | Optics express Vol. 15; no. 17; pp. 10822 - 10831 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
United States
20.08.2007
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Online Access | Get full text |
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Summary: | 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 C(2)H(2) and CO(2) 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 x 10-(11) cm(-1), which corresponds to a detection limit of 4.5 ppt (2 ppt.m) for C(2)H(2), 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 C(2)H(2) and CO(2). |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1094-4087 1094-4087 |
DOI: | 10.1364/OE.15.010822 |