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arXiv · 1909.04361

Cold-atom clock based on a diffractive optic

Rachel Elvin·Gregory W. Hoth·Michael Wright·Ben Lewis·James P. McGilligan·Aidan S. Arnold·Paul F. Griffin·Erling Riis
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Abstract

Clocks based on cold atoms offer unbeatable accuracy and long-term stability, but their use in portable quantum technologies is hampered by a large physical footprint. Here, we use the compact optical layout of a grating magneto-optical trap (gMOT) for a precise frequency reference. The gMOT collects $10^7$ $^{87}$Rb atoms, which are subsequently cooled to $20\,\mu$K in optical molasses. We optically probe the microwave atomic ground-state splitting using lin$\perp$lin polarised coherent population trapping and a Raman-Ramsey sequence. With ballistic drop distances of only $0.5\,$mm, the measured short-term fractional frequency stability is $2 \times 10 ^{-11} /\sqrt{\tau}$.

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Rachel Elvin, Gregory W. Hoth, Michael Wright, Ben Lewis, James P. McGilligan, Aidan S. Arnold, Paul F. Griffin, Erling Riis. 2019-09-10. Cold-atom clock based on a diffractive optic. https://doi.org/10.1364/oe.378632

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