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arXiv · 2006.01306

Optical Atomic Clock Comparison through Turbulent Air

Martha I. Bodine·Jean-Daniel Deschênes·Isaac H. Khader·William C. Swann·Holly Leopardi·Kyle Beloy·Tobias Bothwell·Samuel M. Brewer·Sarah L. Bromley·Jwo-Sy Chen·Scott A. Diddams·Robert J. Fasano·Tara M. Fortier·Youssef S. Hassan·David B. Hume·Dhruv Kedar·Colin J. Kennedy·Amanda Koepke·David R. Leibrandt·Andrew D. Ludlow·William F. McGrew·William R. Milner·Daniele Nicolodi·Eric Oelker·Thomas E. Parker·John M. Robinson·Stefania Romish·Stefan A. Schäffer·Jeffrey A. Sherman·Lindsay Sonderhouse·Jian Yao·Jun Ye·Xiaogang Zhang·Nathan R. Newbury·Laura C. Sinclair
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Abstract

We use frequency comb-based optical two-way time-frequency transfer (O-TWTFT) to measure the optical frequency ratio of state-of-the-art ytterbium and strontium optical atomic clocks separated by a 1.5 km open-air link. Our free-space measurement is compared to a simultaneous measurement acquired via a noise-cancelled fiber link. Despite non-stationary, ps-level time-of-flight variations in the free-space link, ratio measurements obtained from the two links, averaged over 30.5 hours across six days, agree to $6\times10^{-19}$, showing that O-TWTFT can support free-space atomic clock comparisons below the $10^{-18}$ level.

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BibTeXRIS

Martha I. Bodine, Jean-Daniel Deschênes, Isaac H. Khader, William C. Swann, Holly Leopardi, Kyle Beloy, Tobias Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Scott A. Diddams, Robert J. Fasano, Tara M. Fortier, Youssef S. Hassan, David B. Hume, Dhruv Kedar, Colin J. Kennedy, Amanda Koepke, David R. Leibrandt, Andrew D. Ludlow, William F. McGrew, William R. Milner, Daniele Nicolodi, Eric Oelker, Thomas E. Parker, John M. Robinson, Stefania Romish, Stefan A. Schäffer, Jeffrey A. Sherman, Lindsay Sonderhouse, Jian Yao, Jun Ye, Xiaogang Zhang, Nathan R. Newbury, Laura C. Sinclair. 2020-06-01. Optical Atomic Clock Comparison through Turbulent Air. https://doi.org/10.1103/physrevresearch.2.033395

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