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Search Publications by: William C. Swann (Fed)

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Displaying 26 - 50 of 317

High temperature performance of the HITEMP2010 and HITRAN Online databases: comparison with frequency comb measurements of water vapor absorption from 6800 cm-1 to 7200 cm-1

April 3, 2018
Author(s)
Paul J. Schroeder, D Pfotenhauer, J Yang, William C. Swann, Ian R. Coddington, Nathan R. Newbury, Greg B. Rieker
The HITEMP2010 and HITRAN Online databases are important tools for predicting molecular absorption under various environmental conditions. At room temperature the databases can be quite accurate, owing to their development using room temperature absorption

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

November 22, 2017
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 terminals for transmitting precise frequency comb pulses over 10 kilometer scale paths. We

Broadband, high-resolution investigation of advanced absorption lineshapes at high temperature

August 23, 2017
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury, Paul J. Schroeder, Matthew J. Cich, Jinyu Yang, Brian J. Drouin, Gregory B. Rieker
Spectroscopic studies of planetary atmospheres and high-temperature processes (e.g. combustion) require absorption lineshape models that are accurate over extended temperature ranges. To date, advanced lineshapes, like the speed-dependent Voigt and Rautian

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

Fully-Stabilized All Polarization-Maintaining Fiber Erbium Frequency Comb

May 3, 2017
Author(s)
Laura C. Sinclair, Ian R. Coddington, William C. Swann, Kana Iwakuni, Nathan R. Newbury
We demonstrate a completely polarization-maintaining fiber frequency comb operating at a 200 MHz repetition rate and show stability and noise performance consistent with precision measurement applications. This design is compatible with a robust, fieldable

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

Tight real-time synchronization of a microwave clock to an optical clock across a turbulent air path

April 15, 2016
Author(s)
Hugo Bergeron, Laura C. Sinclair, William C. Swann, Craig Nelson, Jean-Daniel Deschenes, Esther Baumann, Fabrizio R. Giorgetta, Ian R. Coddington, Nathan R. Newbury
The ability to distribute the precise time and frequency from an optical clock to remote platforms could enable future precise navigation and sensing systems. Here we demonstrate tight, real-time synchronization of a remote microwave clock to a master

Dual-comb spectroscopy

April 14, 2016
Author(s)
Ian R. Coddington, Nathan R. Newbury, William C. Swann
Dual-comb spectroscopy is an emerging new spectroscopic tool that exploits the frequency resolution, frequency accuracy, broad bandwidth, and brightness of frequency combs for ultra-high resolution, sensitive broadband spectroscopy. By use of two coherent

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