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William C. Swann

Publications

Measurement of the 27Al+ and 87Sr absolute optical frequencies

Author(s)
Holly Leopardi, Kyle Beloy, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Scott Diddams, Robert J. Fasano, Youssef S. Hassan, David B. Hume, Dhruv Kedar, Colin J. Kennedy, Isaac H. Khader, David R. Leibrandt, Andrew D. Ludlow, William F. McGrew, William R. Milner, Daniele Nicolodi, Eric Oelker, Thomas E. Parker, John M. Robinson, Stefania Romisch, Jeffrey A. Sherman, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang, Tara M. Fortier
We perform absolute measurement of the 27Al+ single-ion and 87Sr neutral lattice clock frequencies at the National Institute of Standards and Technology and

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

Patents

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, Nathan R Newbury, William C. Swann and JD Deschenes
Patent Description The invention is a method to compare and synchronize "clocks" (i.e. local timescales) through optical links across free space, which include open air paths through the atmosphere to other terrestrial sites or to satellites, as well as satellite-to-satellite paths. The challenge is
Created October 9, 2019