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Two-Way Link for Time Interval Comparison of Optical Clocks over Free-Space



Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Esther Baumann, Jean-Daniel Deschenes, Laura C. Sinclair, Alexander M. Zolot, Nathan R. Newbury


We demonstrate a free-space link for clock comparisons based on the two-way exchange of pulse trains from combs. The residual uncertainty is 5 * 10^17 in 100 seconds over a 120 m air path, with longer distances possible.
Proceedings Title
Conference on Lasers and Electro-Optics (CLEO)
Conference Dates
May 6-11, 2012
Conference Location
San Jose, CA


frequency comb, frequency transfer, optical clocks


Giorgetta, F. , Swann, W. , Coddington, I. , Baumann, E. , Deschenes, J. , Sinclair, L. , Zolot, A. and Newbury, N. (2012), Two-Way Link for Time Interval Comparison of Optical Clocks over Free-Space, Conference on Lasers and Electro-Optics (CLEO), San Jose, CA, [online], (Accessed June 12, 2024)


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Created May 11, 2012, Updated November 10, 2018