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Search Publications by: William C. Swann (Fed)

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Displaying 76 - 100 of 159

Sensitivity of coherent dual-comb spectroscopy

March 31, 2010
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
Coherent dual comb spectroscopy can provide high-resolution, high-accuracy measurements of a sample response in both magnitude and phase. We discuss the achievable signal-to-noise ratio (SNR) due to both additive white noise and multiplicative noise, and

Infrared time domain spectroscopy with synchronized frequency combs

January 29, 2010
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
We describe a frequency-comb based system for time-domain spectroscopy in the near infrared. Our configuration implements synchronous, repetitive sampling of the time domain signature for real-time coherent signal averaging and improved signal-to-noise

Coherent linear optical sampling at over 15 bits of resolution

July 15, 2009
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury
Linear optical sampling characterizes a sample by measuring the distortions on a transmitted optical field, thereby quantifying the sample's optical response. By exploiting the high mutual coherence between two phase-locked femtosecond fiber lasers, we

Using the nonlinear Schroedinger equation for precision optical measurements

July 6, 2009
Author(s)
Nathan R. Newbury, Esther Baumann, Ian R. Coddington, Fabrizio R. Giorgetta, William C. Swann
Frequency combs produce light that is both broadband and highly coherent. However, their operation relies on the nonlinear Schroedinger equation, in particular to achieve the broad spectral output. Because it is a highly nonlinear system, this comb output

Precision ranging LIDAR using femtosecond fiber lasers

June 17, 2009
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
We discuss a coherent laser radar that uses two coherent femtosecond fiber lasers to perform absolute ranging at long distance. One coherent femtosecond fiber lasers acts as a source and the other as a local oscillator for heterodyne detection of the

Rapid and precise absolute distance measurements at long range

June 1, 2009
Author(s)
Ian R. Coddington, William C. Swann, Ljerka Nenadovic, Nathan R. Newbury
The ability to determine absolute distance to an object is one of the most basic measurements of remote sensing. High precision ranging has important applications in both large-scale manufacturing and in future tight formation-flying satellite missions

Time and Frequency-Domain Spectroscopy with Dual Frequency Combs

May 28, 2009
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
High-resolution spectroscopic measurements of the amplitude and phase spectra from a gas sample can be acquired by use of dual frequency combs. Here we discuss the corresponding gas signature in the time domain.

Absolute Ranging Using Frequency Combs

May 25, 2009
Author(s)
William C. Swann, Ian R. Coddington, Nathan R. Newbury
We present a technique for measuring absolute range that uses two mismatched frequency combs to measure distance over 1.5 m range with 10 nm level statistical uncertainty.

Frequency comb spectroscopy with coherent optical sampling

April 20, 2009
Author(s)
Ian R. Coddington, Nathan R. Newbury, William C. Swann
A stabilized frequency comb provides a broadband array of highly resolved comb lines. Using a multiheterodyne technique, we measure the amplitude and phase of every comb line, allowing for massively parallel, high-resolution spectroscopy.

High-performance, vibration-immune, fiber-laser frequency comb

March 1, 2009
Author(s)
Esther Baumann, Fabrizio R. Giorgetta, Jeffrey W. Nicholson, William C. Swann, Ian R. Coddington, Nathan R. Newbury
We demonstrate an environmentally robust optical frequency comb based on a polarization-maintaining, allfiber, figure-eight laser. The comb is phase locked to a cavity-stabilized cw laser by use of an intracavity electro-optic phase modulator yielding 1.6

Coherent measurements with fiber-laser frequency combs

February 2, 2009
Author(s)
Nathan R. Newbury, Ian R. Coddington, Tasshi Dennis, William C. Swann, Paul A. Williams
The coherent and broad spectral output of fiber-laser frequency combs can be exploited for a variety of high-resolution measurements outside of conventional frequency metrology. We will discuss recent measurements in spectroscopy, ranging, and

Low noise frequency comb based on an all-fiber polarization-maintaining figure-8 laser

February 2, 2009
Author(s)
Esther Baumann, Fabrizio R. Giorgetta, Jeffrey W. Nicholson, William C. Swann, Ian R. Coddington, Nathan R. Newbury
We present a frequency comb based on an all-fiber polarization-maintaining figure-8 laser. It is locked to an optical reference through an intracavity high bandwidth electro-optical modulator and has a flat phase noise of -78 dBc/Hz.

Measuring optical waveforms with fiber frequency combs

January 5, 2009
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury
A stabilized frequency comb provides a broadband array of highly resolved comb lines. Using a multiheterodyne technique, we measure the amplitude and phase of every comb line, allowing for massively parallel, high-resolution optical sampling.

Alpha-Dot or Not: Comparison of Two Single Atom Optical Clocks

October 5, 2008
Author(s)
Till P. Rosenband, David Hume, Chin-Wen Chou, J.C. Koelemeij, A. Brusch, Sarah Bickman, Windell Oskay, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Nathan R. Newbury, William C. Swann, Wayne M. Itano, David J. Wineland, James C. Bergquist
Repeated measurements of the frequency ratio of Hg + and Al + single-atom optical clocks over the course of a year yield a constraint on the possible temporal variation of the fine-structure constant a. The time variation of the measured ratio corresponds

Recent atomic clock comparisions at NIST

October 1, 2008
Author(s)
Luca Lorini, Neil Ashby, Anders Brusch, Scott Diddams, Robert E. Drullinger, Eric Eason, Tara Fortier, Pat Hastings, Thomas P. Heavner, David Hume, Wayne M. Itano, Steven R. Jefferts, Nathan R. Newbury, Tom Parker, Till P. Rosenband, Jason Stalnaker, William C. Swann, David J. Wineland, James C. Bergquist
The record of atomic clock frequency comparisons at NIST over the past half-decade provides one of the tightest constraints of any present-day, temporal variations of the fundamental constants. Notably, the 6-year record of increasingly precise

Ratio of the Al + and Hg + Optical Clock Frequencies to 17 Decimal Places

August 25, 2008
Author(s)
Wayne M. Itano, Till P. Rosenband, David Hume, P.O. Schmidt, Chin-Wen Chou, A. Brusch, Luca Lorini, Windell Oskay, Robert E. Drullinger, Sarah Bickman, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, William C. Swann, Nathan R. Newbury, David J. Wineland, James C. Bergquist
Frequency standards (atomic clocks) based on narrow optical transitions in 27Al + and 199Hg + have been developed over the past several years at NIST. These two types of standards are both based on single ions confined in Paul traps, but differ in the

High-stability transfer of an optical frequency over long fiber-optic links

August 1, 2008
Author(s)
Paul A. Williams, William C. Swann, Nathan R. Newbury
We present theoretical predictions and experimental measurements for the achievable phase noise, timing jitter, and frequency stability in the coherent transport of an optical frequency over a fiber-optic link. Both technical and fundamental limitations to

Applications of highly coherent femtosecond fiber lasers

July 13, 2008
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
Coherent, broadband fiber lasers produce pulse trains with <1 femtosecond relative timing uncertainty and <1 mHz relative frequency uncertainty. These sources can advance many applications including optical frequency metrology, ranging LIDAR, and broadband

High resolution spectroscopy using fiber-laser frequency combs

June 8, 2008
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury
The output of a femtosecond fiber laser can be both spectrally broadened and stabilized, thereby providing a broadband coherent source in the near infrared. In the frequency domain, the result is a frequency comb with frequency stabilities at the