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arXiv · 2207.12976

A grating-chip atomic fountain

Ben Lewis·Rachel Elvin·Aidan S. Arnold·Erling Riis·Paul F. Griffin
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Abstract

Cold atom fountain clocks provide exceptional long term stability as they increase interrogation time at the expense of a larger size. We present a compact cold atom fountain using a grating magneto-optical trap (GMOT) to laser cool and launch the atoms in a simplified optical setup. The fountain is evaluated using coherent population trapping and demonstrates improved single-shot stability from the launch. Ramsey times up to 100 ms were measured with a corresponding fringe linewidth of 5 Hz. This technique could improve both short- and long-term stability of cold atom clocks whilst remaining compact for portable applications.

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Ben Lewis, Rachel Elvin, Aidan S. Arnold, Erling Riis, Paul F. Griffin. 2022-07-26. A grating-chip atomic fountain. https://doi.org/10.1063/5.0115382

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