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arXiv · 1612.08647

Fully Stabilized Mid-Infrared Frequency Comb for High-Precision Molecular Spectroscopy

Markku Vainio·Juho Karhu
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Abstract

A fully stabilized mid-infrared optical frequency comb spanning from 2.9 to 3.4 um is described. The comb is based on half-harmonic generation in a femtosecond optical parametric oscillator, which transfers the high phase coherence of a fully stabilized near-infrared Er-doped fiber laser comb to the mid-infrared region. The method is simple, as no phase-locked loops or reference lasers are needed. Precise locking of optical frequencies of the mid-infrared comb to the pump comb is experimentally verified at sub-20 mHz level, which corresponds to a fractional statistical uncertainty of 2x10-16 at the center frequency of the mid-infrared comb. The fully stabilized mid-infrared comb is an ideal tool for high-precision molecular spectroscopy, as well as for optical frequency metrology in the mid-infrared region, which is difficult to access with other stabilized frequency comb techniques.

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Markku Vainio, Juho Karhu. 2016-12-27. Fully Stabilized Mid-Infrared Frequency Comb for High-Precision Molecular Spectroscopy. https://doi.org/10.1364/oe.25.004190

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