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arXiv · 1705.04214

A phase-stable dual-comb interferometer

Zaijun Chen·Ming Yan·Theodor W. Hänsch·Nathalie Picqué
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Abstract

Improvements to dual-comb interferometers will benefit precision spectroscopy and sensing, distance metrology, tomography, telecommunications etc. A specific requirement of such interferometers is to enforce mutual coherence between the two combs over the measurement time. With feed-forward relative stabilization of the carrier-enveloppe offset frequencies, we experimentally realize such mutual coherence over times that exceed 300 seconds, two orders of magnitude longer than state-of-the-art systems. Illustration is given with near-infrared Fourier transform molecular spectroscopy, where two combs of slightly different repetition frequencies replace a scanning two-beam interferometer. Our technique can be implemented with any frequency comb generators including microresonators or quantum cascade lasers.

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Zaijun Chen, Ming Yan, Theodor W. Hänsch, Nathalie Picqué. 2017-05-11. A phase-stable dual-comb interferometer. https://doi.org/10.1038/s41467-018-05509-6

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