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PubMed · 11543546

Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy.

A A Kosterev·R F Curl·F K Tittel·C Gmachl·F Capasso·D L Sivco·J N Baillargeon·A L Hutchinson·A Y Cho
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Abstract

A variable duty cycle quasi-cw frequency scanning technique was applied to reduce thermal effects resulting from the high heat dissipation of type I quantum-cascade lasers. This technique was combined with a 100-m path-length multipass cell and a zero-air background-subtraction technique to enhance detection sensitivity to a parts-in-10(9) (ppb) concentration level for spectroscopic trace-gas detection of CH4, N2O, H2O, and C2H5OH in ambient air at 7.9 micrometers. A new technique for analysis of dense high resolution absorption spectra was applied to detection of ethanol in ambient air, yielding a 125-ppb detection limit.

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Air Pollution, IndoorEnvironmental MonitoringEquipment DesignEthanolEvaluation Studies as TopicGasesLasersLinear ModelsMethaneNitrous OxideSpectrophotometry, AtomicTemperatureWaterNASA Discipline Environmental HealthNon-NASA CenterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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A A Kosterev, R F Curl, F K Tittel, C Gmachl, F Capasso, D L Sivco, J N Baillargeon, A L Hutchinson, A Y Cho. 2000-08-20. Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy.. https://doi.org/10.1364/ao.39.004425

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