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Mid-infrared trace gas detection using continuous-wave difference frequency generation in periodically poled RbTiOAsO4.

W Chen·G Mouret·D Boucher·F K Tittel
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Abstract

A tunable mid-infrared continuous-wave (cw) spectroscopic source in the 3.4-4.5 micrometers region is reported, based on difference frequency generation (DFG) in a quasi-phase-matched periodically poled RbTiOAsO4 (PPRTA) crystal. DFG power levels of 10 microW were generated at approximately 4 micrometers in a 20-mm long PPRTA crystal by mixing two cw single-frequency Ti:Al2O3 lasers operating near 713 nm and 871 nm, respectively, using a laser pump power of 300 mW. A quasi-phase-matched infrared wavelength-tuning bandwidth (FWHM) of ~ 12 cm-1 and a temperature tuning rate of 1.02 cm-1/degree C were achieved. Experimental details regarding the feasibility of trace gas detection based on absorption spectroscopy of CO2 in ambient air using this DFG radiation source are also described.

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Aluminum OxideArsenatesCarbon DioxideCrystallizationEnvironmental MonitoringGasesLasersNormal DistributionOptics and PhotonicsRubidiumSpectrophotometry, InfraredTitaniumNASA Discipline Life Sciences TechnologiesNon-NASA CenterJournal ArticleResearch Support, Non-U.S. Gov't

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W Chen, G Mouret, D Boucher, F K Tittel. 2001. Mid-infrared trace gas detection using continuous-wave difference frequency generation in periodically poled RbTiOAsO4.. https://doi.org/10.1007/s003400100561

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