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Displaying 26 - 50 of 235

Measurement of the impact of turbulence anisoplanatism on precision free-space optical time transfer

February 27, 2019
Author(s)
William C. Swann, Martha I. Bodine, Isaac H. Khader, Jean-Daniel Deschenes, Esther Baumann, Laura C. Sinclair, Nathan R. Newbury
Future highly precise free-space optical clock networks will require optically-based two-way time and frequency transfer links. As these networks extend over longer distances, they will include links between moving platforms, e.g. ground-to-air or ground

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

Mid-infrared dual-comb spectroscopy of volatile organic compounds across long open-air paths

February 5, 2019
Author(s)
Gabriel Ycas, Fabrizio Giorgetta, Kevin Cossel, Eleanor M. Waxman, Esther Baumann, Nathan R. Newbury, Ian Coddington
Open-path measurements of atmospheric gas species in the air, including volatile organic compounds, are essential to quantify emissions from sources like oil and gas, forest fires, and industry. Here, we extend open-path dual-comb spectroscopy to probe the

Real-time liquid-phase organic reaction monitoring with a mid-infrared dual frequency comb spectrometer

January 10, 2019
Author(s)
Daniel I. Herman, Eleanor M. Waxman, Gabriel G. Ycas, Fabrizio R. Giorgetta, Nathan R. Newbury, Ian R. Coddington
We combine high-resolution mid-infrared dual-comb spectroscopy with attenuated total reflectance measurements to provide in-situ monitoring of a chemical reaction. The mid-infrared dual-comb spectrometer measures quantitative absorption cross-sections of

Time Synchronization over a Free-Space Optical Communication Channel

December 20, 2018
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 communication system and use it directly for two-way time transfer. We demonstrate real-time

Fully self-referenced frequency comb consuming 5 Watts of electrical power

September 12, 2018
Author(s)
Paritosh Manurkar, Edgar F. Perez, Daniel D. Hickstein, David R. Carlson, Jeffrey T. Chiles, Daron A. Westly, Esther Baumann, Scott A. Diddams, Nathan R. Newbury, Kartik A. Srinivasan, Scott B. Papp, Ian R. Coddington
We present a hybrid fiber/waveguide design for a 100-MHz frequency comb that is fully self- referenced and temperature controlled with less than 5 W of electrical power. Self-referencing is achieved by supercontinuum generation in a silicon nitride

An Integrated-Photonics Optical-Frequency Synthesizer

May 3, 2018
Author(s)
Daryl T. Spencer, Tara E. Drake, Travis Briles, Jordan R. Stone, Laura C. Sinclair, Connor D. Fredrick, Qing Li, Daron A. Westly, Bojan R. Ilic, Aaron Bluestone, Nicolas Volet, Tin Komljenovic, Seung Hoon Lee, Dong Yoon Oh, Myoung-Gyun Suh, Ki Youl Yang, Martin H. Pfeiffer, Tobias J. Kippenberg, Erik Norberg, Kerry Vahala, Kartik A. Srinivasan, Nathan R. Newbury, Luke Theogarajan, John E. Bowers, Scott A. Diddams, Scott B. Papp
Integrated-photonics microchips now enable a range of advanced functionalities for high- coherence applications like data transmission, for highly optimized physical sensors, and for harnessing quantum states, but with size, extensibility, and portability

Femtosecond timekeeping: slip-free optical clockwork for optical timescales

April 3, 2018
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-fidelity time output. We demonstrate comb-based clockwork that phase-coherently integrates ~7x10e20

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

Ultrabroadband Supercontinuum Generation and Frequency-Comb Stabilization Using On-Chip Waveguides with Both Cubic and Quadratic Nonlinearities

July 24, 2017
Author(s)
Daniel D. Hickstein, Hojoong Jung, David R. Carlson, Alexander J. Lind, Ian R. Coddington, Kartik A. Srinivasan, Gabriel G. Ycas, Daniel C. Cole, Abijith S. Kowligy, Stefan Droste, Erin S. Lamb, Nathan R. Newbury, Hong X. Tang, Scott A. Diddams, Scott B. Papp
Using aluminum-nitride photonic-chip waveguides, we generate optical frequency comb supercontinuum spanning 500~nm to 4000~nm, and show that the spectrum can be widely tailored by changing the geometry of the waveguide. Since aluminum nitride exhibits both

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

Wake Mode Sidebands and Instability of Modelocked Lasers with Slow Saturable Absorbers

June 14, 2017
Author(s)
Shaokang Wang, Stefan Droste, Laura C. Sinclair, Ian R. Coddington, Nathan R. Newbury, Curtis R. Menyuk
Passively modelocked lasers with semiconductor saturable absorption mirrors (SESAMs) are attractive comb sources since they can be made environmentally stable, but they become unstable when the group velocity dispersion is too low or the gain is too high

Self-referenced frequency combs using high-efficiency silicon nitride waveguides

June 12, 2017
Author(s)
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Stefan Droste, Daron A. Westly, Nima Nader, Ian R. Coddington, Nathan R. Newbury, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
We utilize silicon nitride waveguides to self-reference telecom-wavelength fiber frequency combs through supercontinuum generation using less than 15 mW total optical average power. This is approximately ten times lower than conventional approaches using

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

Room-temperature-deposited dielectrics and superconductors for integrated photonics

May 1, 2017
Author(s)
Jeffrey M. Shainline, Sonia M. Buckley, Nima Nader, Cale M. Gentry, Kevin C. Cossel, Milos A. Popovic, Nathan R. Newbury, Richard P. Mirin
We present an approach to fabrication and packaging of integrated photonic devices that utilizes waveguide and detector layers deposited at near-ambient temperature. All lithography is performed with a 365 nm i-line stepper, facilitating low cost and high

Gas-phase broadband spectroscopy using active sources: progress, status, and applications

January 1, 2017
Author(s)
Kevin C. Cossel, Eleanor M. Waxman, Ian A. Finneran, Geoffery A. Blake, Jun Ye, Nathan R. Newbury
Broadband spectroscopy is an invaluable tool for measuring multiple gas-phase species simultaneously. In this work we review current applications for broad-band spectroscopy. We discuss components of broad-band spectroscopy including light sources

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