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Search Publications by William C. Swann

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Displaying 1 - 25 of 144

Femtosecond Time Synchronization of Optical Clocks Off a Flying Quadcopter

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

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

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

Time Synchronization over a Free-Space Optical Communication Channel

Author(s)
Isaac H. Khader, Laura C. Sinclair, William C. Swann, Hugo Bergeron, Nathan R. Newbury, Jean-Daniel Deschenes
Free space optical (FSO) communication channels are typically used to transmit high-speed data between sites over the air. Here we repurpose an FSO digital

Femtosecond timekeeping: slip-free optical clockwork for optical timescales

Author(s)
Daniel I. Herman, Stefan Droste, Esther Baumann, Jonathan Roslund, Dmitriy Churin, Arman Cingoz, Jean-Daniel Deschenes, Isaac H. Khader, William C. Swann, Craig W. Nelson, Nathan R. Newbury, Ian R. Coddington
The generation of true optical time standards will require the conversion of the highly stable optical frequency output of an optical atomic clock to a high

Low-Loss Reciprocal Optical Terminals for Two-Way Time-Frequency Transfer

Author(s)
William C. Swann, Laura C. Sinclair, Isaac H. Khader, Nathan R. Newbury, Jean-Daniel Deschenes, Hugo Bergeron
Optical two-way time-frequency transfer (O-TWTFT) over atmospheric free-space paths requires low- loss, single-mode, bi-directional and fully reciprocal optical

Open-path dual-comb spectroscopy to an airborne retroreflector

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

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

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

Optical system design for femtosecond-level synchronization of clocks

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

Femtosecond synchronization of optical clocks over free-space links

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

Broadband phase spectroscopy over turbulent air paths

Author(s)
Fabrizio R. Giorgetta, Greg B. Rieker, Esther Baumann, William C. Swann, Laura C. Sinclair, Jonathan Kofler, Ian R. Coddington, Nathan R. Newbury
Broadband atmospheric phase spectra are measured at sub-milliradian uncertainty corresponding to a 10-13 refractive index change, despite strong decoherence

A compact optically coherent fiber frequency comb

Author(s)
Laura C. Sinclair, Jean-Daniel Deschenes, Lindsay I. Sonderhouse, William C. Swann, Isaac H. Khader, Esther Baumann, Nathan R. Newbury, Ian R. Coddington
We describe design and operation of a robust self-referenced, optically coherent frequency comb. The system robustness is derived from a combination of an

Frequency-Comb-Based Remote Sensing of Greenhouse Gases over Kilometer Air Paths

Author(s)
Greg B. Rieker, Fabrizio R. Giorgetta, William C. Swann, Jonathan Kofler, Alexander M. Zolot, Laura C. Sinclair, Esther Baumann, Christopher L. Cromer, G. Petron, Colm Sweeney, P P. Tans, Ian R. Coddington, Nathan R. Newbury
We demonstrate frequency comb tooth-by-tooth measurements of atmospheric gas absorption across a 2-km, turbulent, open-air path through coherent dual-comb