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arXiv · 2510.09560

Two-photon rubidium clock detecting 776~nm fluorescence

River Beard·Kyle W. Martin·John D. Elgin·Brian L. Kasch·Sean P. Krzyzewski
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Abstract

The optical atomic clock based on the $5S_{1/2} \rightarrow 5D_{5/2}$ two-photon transition in rubidium is a candidate for a next generation, manufacturable, portable clock that fits in a small size, weight, and power (SWaP) envelope. Here, we report the first two-photon rubidium clock stabilized by detecting 776~nm fluorescence. We also demonstrate the use of a multi-pixel photon counter as a low voltage substitute to a photomultiplier tube in the feedback loop to the clock laser.

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River Beard, Kyle W. Martin, John D. Elgin, Brian L. Kasch, Sean P. Krzyzewski. 2025-10-10. Two-photon rubidium clock detecting 776~nm fluorescence. https://doi.org/10.1364/oe.513974

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