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arXiv · 1511.06708

Ultrastable frequency reference at 1.56 μm using a CO molecular overtone transition with the noise immune cavity-enhanced optical heterodyne molecular spectroscopy method

Shailendar Saraf·Paul Berceau·Alberto Stochino·Robert Byer·John Lipa
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Abstract

We report on an ultrastable molecular clock based on the interrogation of the 3ν rotational-vibrational combination band at 1563nm of carbon monoxide 12C16O. The laser stabilization scheme is based on frequency modulation (FM) saturation spectroscopy in a high-finesse ultra-low expansion (ULE) glass optical cavity using CO as the molecular reference for longterm stabilization of the cavity resonance. The NICEOHMS FM modulation method is employed to maintain a high signal-to-noise ratio and avoid conversion of laser frequency noise into amplitude noise by the high finesse cavity. We report an Allan Deviation of 1.8x10-12 at 1 second that improves to 3.5x10-14 after 1000 seconds of averaging.

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Shailendar Saraf, Paul Berceau, Alberto Stochino, Robert Byer, John Lipa. 2016-04-11. Ultrastable frequency reference at 1.56 μm using a CO molecular overtone transition with the noise immune cavity-enhanced optical heterodyne molecular spectroscopy method. https://doi.org/10.1364/ol.41.002189

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