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William C. Swann (Fed)

Publications

Quantum-limited optical time transfer for future geosynchronous links

Author(s)
Emily Caldwell, Jean-Daniel Deschenes, Jennifer Ellis, William C. Swann, Benjamin Stuhl, Hugo Bergeron, Nathan R. Newbury, Laura Sinclair
The combination of optical time transfer and optical clocks opens up the possibility of large-scale free-space networks that connect both ground-based optical

Photon Efficient Optical Time Transfer

Author(s)
Emily Caldwell, Laura Sinclair, William C. Swann, Nathan R. Newbury, Benjamin Stuhl, Jean-Daniel Deschenes
We present a novel frequency comb-based system for optical two-way time-frequency transfer to support very long distance free-space links between clocks. Our

Frequency Ratio Measurements with 18-Digit Accuracy Using a Network of Optical Clocks

Author(s)
Kyle Beloy, Martha I. Bodine, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Jean-Daniel Deschenes, Scott Diddams, Robert J. Fasano, Tara Fortier, Youssef Hassan, David Hume, Dhruv Kedar, Colin J. Kennedy, Isaac Kader, Amanda Koepke, David Leibrandt, Holly Leopardi, Andrew Ludlow, Will McGrew, William Milner, Daniele Nicolodi, Eric Oelker, Tom Parker, John M. Robinson, Stefania Romisch, Stefan A. Schaeffer, Jeffrey Sherman, Laura Sinclair, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang
Atomic clocks occupy a unique position in measurement science, exhibiting higher accuracy than any other measurement standard and underpinning six out of seven
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Patents (2018-Present)

Synchronizer And Synchronizing Transfer Over An Optical Link

NIST Inventors
Laura Sinclair , William C. Swann and JD Deschenes
A synchronizer for synchronizing transfer over an optical link includes a frequency reference oscillator; a tracking optical timing source; a tracking comb signal; a signal processor-controller; a comb timing discriminator; a clock frequency comb; a bidirectional terminal; a time-frequency offset
Powerpoint slide, showing via map and photograhpy, the distance from NIST Boulder to Valmont Butte

Optical Time Distributor and Process for Optical Two-Way Time-Frequency Transfer

NIST Inventors
Laura Sinclair , William C. Swann and JD Deschenes
An optical time distributor includes: a master clock including: a master comb; a transfer comb; and a free-space optical terminal; and a remote clock in optical communication with the master clock via a free space link and including: a remote comb that produces: a remote clock coherent optical pulse
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Created October 9, 2019, Updated December 8, 2022