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Next-Generation Chip-Scale Atomic Clocks



John Kitching, Matthew Hummon, William McGehee, Ying-Ju Wang, Susan Schima


We describe work toward the development of next-generation chip-scale atomic clocks, which combine small size, low power consumption and manufacturability with high frequency stability. The use of optical transitions in microfabricated vapor cells improves both short- and long-term frequency stability to near 10-13 at the cost of the added complexity of a chip-scale optical frequency comb. Chip-scale atomic beam microwave clocks have been successfully demonstrated and offer the potential for microsecond-level timing accuracy over one week. Sr vapor cells have been developed with lifetimes exceeding 250 hours and residual gas pressures below 1 Torr.
Proceedings Title
Proceedings of the 9th Symposium on Frequency Standards and Metrology
Conference Dates
October 16-20, 2023
Conference Location
Kingscliff, AU
Conference Title
9th Symposium on Frequency Standards and Metrology


Atomic clock, chip-scale atomic clock, optical clock, atomic beam clock, microfabrication


Kitching, J. , Hummon, M. , McGehee, W. , Wang, Y. and Schima, S. (2023), Next-Generation Chip-Scale Atomic Clocks, Proceedings of the 9th Symposium on Frequency Standards and Metrology, Kingscliff, AU, [online], (Accessed June 25, 2024)


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Created October 16, 2023, Updated June 7, 2024