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Displaying 1 - 6 of 6

Femtosecond Time Synchronization of Optical Clocks Off a Flying Quadcopter

April 18, 2019
Author(s)
Hugo Bergeron, Laura C. Sinclair, William C. Swann, Isaac H. Khader, Kevin C. Cossel, Michael A. Cermak, Jean-Daniel Deschenes, Nathan R. Newbury
Optical clock networks promise advances in global navigation, time distribution, coherent sensing, relativity experiments, dark matter searches and other areas1-12. Such networks will need to compare and synchronize clocks over free-space optical links

Femtosecond Optical Two-Way Time-Frequency Transfer in the Presence of Motion

February 22, 2019
Author(s)
Laura C. Sinclair, Hugo Bergeron, William C. Swann, Isaac H. Khader, Kevin C. Cossel, Michael A. Cermak, Nathan R. Newbury, Jean-Daniel Deschenes
Platform motion poses significant challenges to high-precision optical time and frequency transfer. We give a detailed description of these challenges and their solutions in comb-based optical two-way time and frequency transfer (O-TWTFT). Specifically, we

Open-path dual-comb spectroscopy to an airborne retroreflector

July 20, 2017
Author(s)
Kevin C. Cossel, Eleanor M. Waxman, Fabrizio R. Giorgetta, Michael A. Cermak, Dan Hesselius, Shalom Ruben, William C. Swann, Gregory B. Rieker, Nathan R. Newbury
We demonstrate a new technique for spatial mapping of multiple atmospheric gas species. This system is based on high-precision dual-comb spectroscopy to a retroreflector mounted on a flying multicopter. We measure the atmospheric absorption over long open

Synchronization of clocks through 12km of strongly turbulent air over a city

October 11, 2016
Author(s)
Laura C. Sinclair, William C. Swann, Hugo Bergeron, Esther Baumann, Michael A. Cermak, Ian R. Coddington, Jean-Daniel Deschenes, Fabrizio R. Giorgetta, Juan Juarez, Isaac H. Khader, Keith G. Petrillo, Katherine T. Souza, Michael L. Dennis, Nathan R. Newbury
We demonstrate real-time, femtosecond-level clock synchronization across a low-lying, strongly turbulent, 12-km horizontal air path by optical two-way time transfer. For this long horizontal free-space path, the integrated turbulence extends well into the

Optical system design for femtosecond-level synchronization of clocks

February 13, 2016
Author(s)
Laura C. Sinclair, William C. Swann, Jean-Daniel Deschenes, Hugo Bergeron, Fabrizio R. Giorgetta, Esther Baumann, Michael A. Cermak, Ian R. Coddington, Nathan R. Newbury
Synchronization of optical clocks via optical two-way time-frequency transfer across free-space links can result in time offsets between the two clocks below tens of femtoseconds over many hours. The complex optical system necessary to support such

Femtosecond synchronization of optical clocks over free-space links

December 11, 2015
Author(s)
Jean-Daniel Deschenes, Laura C. Sinclair, Fabrizio R. Giorgetta, William C. Swann, Esther Baumann, Hugo Bergeron, Michael A. Cermak, Nathan R. Newbury
The use of optical clocks/oscillators in future ultra-precise navigation, gravitational sensing, and relativity experiments will require time comparison and synchronization over terrestrial or satellite free-space links. Here we demonstrate full