Compact CH4 sensor based on difference frequency mixing of diode lasers in quasi-phasematched LiNbO3

Lancaster, D. G.; Weidner, R.; Richter, D.; Tittel, F. K.; Limpert, J.

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Compact CH4 sensor based on difference frequency mixing of diode lasers in quasi-phasematched LiNbO3

Lancaster, D. G.·Weidner, R.·Richter, D.·Tittel, F. K.·Limpert, J.

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Abstract

A compact, portable and robust room temperature CH4 sensor is reported. By difference frequency mixing a 500 mW alpha-DFB diode laser at 1066 nm and an erbium-doped fiber amplified 1574 nm DFB diode laser in periodically poled lithium niobate up to 7 (mu)W of narrowband radiation at 3.3 microns is generated. Real-time monitoring of CH4 over a 7 day period using direct absorption in an open-path multipass cell (L = 36 m) demonstrates a detection precision of +/- 14 ppb.

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NASA Discipline Environmental Health Non-NASA Center Environmental Monitoring/instrumentation Fiber Optics Methane/analysis Lasers Oxides/chemistry Niobium/chemistry Evaluation Studies Calibration Time Factors Support, U.S. Gov't, Non-P.H.S Support, Non-U.S. Gov't Equipment Design Spectrum Analysis

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Lancaster, D. G., Weidner, R., Richter, D., Tittel, F. K., Limpert, J.. 2000-03-01. Compact CH4 sensor based on difference frequency mixing of diode lasers in quasi-phasematched LiNbO3. https://ntrs.nasa.gov/citations/20040088822

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