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arXiv · 1411.2657

Open-Air, Broad-Bandwidth Trace-Gas Sensing with a Mid-Infrared Optical Frequency Comb

Lora Nugent-Glandorf·Fabrizio Giorgetta·Scott A. Diddams
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Abstract

A mid-Infrared frequency comb is produced via an optical parametric oscillator (OPO) pumped by an amplified 100 MHz Yb:fiber mode-locked laser. We use this source to make measurements of the concentration of the atmospherically-relevant species of CH4 and H2O over a bandwidth of 100 nm centered at 3.25 um. Multiple absorption lines for each species are detected with millisecond acquisition time using a virtually-imaged phased array (VIPA) spectrometer. The measured wavelength-dependent absorption profile is compared to and fitted by a model, yielding quantitative values of the atmospheric concentration of both CH4 and H2O in a controlled indoor environment, as well as over a 26 m open air outdoor path.

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Lora Nugent-Glandorf, Fabrizio Giorgetta, Scott A. Diddams. 2014-11-10. Open-Air, Broad-Bandwidth Trace-Gas Sensing with a Mid-Infrared Optical Frequency Comb. https://doi.org/10.1007/s00340-015-6070-8

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