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arXiv · 1404.1162

A widely tunable 10-$μ$m quantum cascade laser phase-locked to a state-of-the-art mid-infrared reference for precision molecular spectroscopy

Papa Lat Tabara Sow·Sinda Mejri·Sean K. Tokunaga·Olivier Lopez·Andrey Goncharov·Bérengère Argence·Christian Chardonnet·Anne Amy-Klein·Christophe Daussy·Benoît Darquié
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Abstract

We report the coherent phase-locking of a quantum cascade laser (QCL) at 10-$μ$m to the secondary frequency standard of this spectral region, a CO2 laser stabilized on a saturated absorption line of OsO4. The stability and accuracy of the standard are transferred to the QCL resulting in a line width of the order of 10 Hz, and leading to our knowledge to the narrowest QCL to date. The locked QCL is then used to perform absorption spectroscopy spanning 6 GHz of NH3 and methyltrioxorhenium, two species of interest for applications in precision measurements.

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Papa Lat Tabara Sow, Sinda Mejri, Sean K. Tokunaga, Olivier Lopez, Andrey Goncharov, Bérengère Argence, Christian Chardonnet, Anne Amy-Klein, Christophe Daussy, Benoît Darquié. 2014-04-04. A widely tunable 10-$μ$m quantum cascade laser phase-locked to a state-of-the-art mid-infrared reference for precision molecular spectroscopy. https://doi.org/10.1063/1.4886120

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