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arXiv · 1508.03284

Mid-Infrared Optical Frequency Combs based on Difference Frequency Generation for Molecular Spectroscopy

Flavio C. Cruz·Daniel L. Maser·Todd Johnson·Gabriel Ycas·Andrew Klose·Fabrizio R. Giorgetta·Ian Coddington·Scott A. Diddams
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Abstract

Mid-infrared femtosecond optical frequency combs were produced by difference frequency generation of the spectral components of a near-infrared comb in a 3-mm-long MgO:PPLN crystal. We observe strong pump depletion and 9.3 dB parametric gain in the 1.5 \mu m signal, which yields powers above 500 mW (3 \mu W/mode) in the idler with spectra covering 2.8 \mu m to 3.5 \mu m. Potential for broadband, high-resolution molecular spectroscopy is demonstrated by absorption spectra and interferograms obtained by heterodyning two combs.

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Flavio C. Cruz, Daniel L. Maser, Todd Johnson, Gabriel Ycas, Andrew Klose, Fabrizio R. Giorgetta, Ian Coddington, Scott A. Diddams. 2015-08-13. Mid-Infrared Optical Frequency Combs based on Difference Frequency Generation for Molecular Spectroscopy. https://doi.org/10.1364/oe.23.026814

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