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High-performance, compact optical standard



Zachary Newman, Vincent N. Maurice, Tara Fortier, Connor Fredrick, Scott Diddams, John Kitching, Matthew Hummon


We describe a high-performance, compact optical frequency standard based on a microfabricated Rb vapor cell and a low-noise, external cavity diode laser operating on the Rb two-photon transition at 778 nm. The optical standard achieves an instability of 1.8×10−13−1/2 for times less than 100 s and a flicker noise floor of 1×10−14 out to 6000 s. At long integration times, the instability is limited by variations in optical probe power and the ac Stark shift. The retrace was measured to 5.7×10−13 after 30 h of dormancy. Such a simple, yet high-performance optical standard could be suitable as an accurate realization of the meter or, if coupled with an optical frequency comb, as a compact atomic clock comparable to a hydrogen maser.
Optics Letters


optical clock, spectroscopy, compact atomic clock, MEMS vapor cell, chip-scale


Newman, Z. , Maurice, V. , Fortier, T. , Fredrick, C. , Diddams, S. , Kitching, J. and Hummon, M. (2021), High-performance, compact optical standard, Optics Letters, [online], (Accessed April 23, 2024)
Created September 15, 2021, Updated March 25, 2024