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Search Publications by: William C. Swann (Fed)

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Displaying 101 - 125 of 159

Broadband, frequency comb spectroscopy

May 4, 2008
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 spectroscopy.

Practical performance limits on optical frequency transfer over fiber optic links

May 4, 2008
Author(s)
Paul A. Williams, William C. Swann, Nathan R. Newbury
We present theory and experiment quantifying the limitations to stable transport of optical frequencies over optical fiber. These are fundamental fiber noise, propagation delay, bidirectional propagation and system noise in the measurement interferometers.

Fiber lasers for frequency standards in optical communications

February 24, 2008
Author(s)
Nathan R. Newbury, William C. Swann, Ian R. Coddington, Paul A. Williams
Optical light with millihertz relative frequency stabilities and subfemtosecond timing jitter can be produced from stabilized cw or mode-locked fiber lasers. We will discuss the generation, fiber-optic distribution and some applications of these coherent

Coherent, multiheterodyne spectroscopy using stabilized optical frequency combs

January 2, 2008
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury
The broadband, coherent nature of narrow-linewidth fiber frequency combs is exploited to measure the full complex spectrum of a molecular gas through multiheterodyne spectroscopy. We measure the absorption and phase shift experienced by each of 155 000

Coherent transfer of an optical carrier over 251 km

October 15, 2007
Author(s)
Nathan R. Newbury, Paul A. Williams, William C. Swann
We transfer of an optical frequency over 251 km of optical fiber with a residual instability of 6×10 -19 at 100 s. This instability and the associated timing jitter are limited fundamentally by the noise on the optical fiber and link length. We give a

Narrow linewidth fiber laser frequency combs

October 15, 2007
Author(s)
William C. Swann, Ian R. Coddington, John Mcferran, Nathan R. Newbury
Fiber laser frequency combs can provide a series of optical lines that span the spectrum from 1 to 2 υm. By tightly locking the frequency comb to an optical reference, it is possible for these comb lines to exhibit residual linewidths below 1 Hz and

Coherent fiber-based frequency combs and cw lasers at 1550 nm

August 26, 2007
Author(s)
Nathan R. Newbury, William C. Swann, Ian R. Coddington, Paul A. Williams
Coherent optical sources in the 1550 nm region of the spectrum have a number of applications in frequency metrology, stable frequency transfer, precision spectroscopy and remote sensing. A narrow-linewidth (~ 1 Hz) single-frequency source can be generated

Narrow linewidth 1.5 ym sources and the thermal limit

July 23, 2007
Author(s)
William C. Swann, Nathan R. Newbury
A measured 1 Hz linewidth between a cavity-stabilized, 1535 nm cw fiber laser and the 1535-nm tooth of a stabilized fiber frequency comb is below the thermodynamic limit of the frequency comb.

Low-noise fiber-laser frequency combs

July 19, 2007
Author(s)
Nathan R. Newbury, William C. Swann
We discuss experimental and theoretical aspects of a low-noise fiber-laser frequency comb, including the experimental configuration and the major contributions to the frequency noise and linewidth of the individual comb modes. Intra-cavity noise sources

Lidar with femtosecond fiber-laser frequency combs

July 8, 2007
Author(s)
Nathan R. Newbury, William C. Swann, Ian R. Coddington
Passively mode-locked fiber lasers produce a broad spectrum of light that is also highly phase-coherent. Such sources have clear potential for remote sensing because their broad spectrum permits high range resolution and the coherence permits operation at

Fiber laser-based frequency combs with high relative frequency stability

May 28, 2007
Author(s)
Nathan R. Newbury, William C. Swann, Ian R. Coddington, J. C. Bergquist, Scott Diddams, Luca Lorini
We describe our current low-noise fiber-laser frequency comb and present measurements of its residual instability. Through a comparison with a Ti:Sapphire frequency comb, we measure residual fractional frequency instabilities (Allan deviation) of 6x10 -17

Fiber-laser frequency combs

May 6, 2007
Author(s)
Nathan R. Newbury, William C. Swann
We discuss the contributions to the linewidth and frequency noise of the individual modes of a mode-locked fiber laser. Much of this noise can be suppressed through feedback to form a stable frequency comb.

Multi-octave optical coherence spanning hundreds of meters

May 6, 2007
Author(s)
Ian R. Coddington, Luca Lorini, William C. Swann, J. C. Bergquist, Y. Le Coq, C. W. Oates, Qudsia Quraishi, Jason Stalnaker, Scott Diddams, Nathan R. Newbury
We demonstrate coherent transfer of optical signals with radian level noise (in a 3.5 MHz bandwidth) through a series of laser systems spanning from 657 nm to 1535 nm and several hundred meter distances.

Residual stability of a fiber-based frequency comb

May 6, 2007
Author(s)
William C. Swann, Ian R. Coddington, Luca Lorini, Jason Stalnaker, J. C. Bergquist, Scott Diddams, Nathan R. Newbury
Abstract: We present measurements of the residual frequency stability across a fiber frequency comb by comparison through a Ti:sapphire frequency comb. We find 6 x 10 -17 stability at one second and 1 x 10 -18 at 1000 seconds.

Coherent optical link over hundreds of metres and hundreds of terahertz with subfemtosecond timing jitter

May 1, 2007
Author(s)
Ian R. Coddington, William C. Swann, Luca Lorini, J. C. Bergquist, K Feder, Y. Le Coq, Jeffrey W. Nicholson, C. W. Oates, Qudsia Quraishi, Paul S. Westbrook, Scott Diddams, Nathan R. Newbury
Recent developments in stabilized lasers have resulted in ultrastable optical oscillators with spectral purities below 1 Hz refs 1-6. These oscillators are not transportable at present and operate at a single frequency. To realize their full potential, a

Radian-level coherent optical links over 100's of meters and 100's of terahertz

January 18, 2007
Author(s)
Ian R. Coddington, Qudsia Quraishi, Luca Lorini, William C. Swann, J. C. Bergquist, C. W. Oates, Scott Diddams, Nathan R. Newbury
We demonstrate coherent transfer of optical signals with radian level noise (in a 25 MHz bandwidth) through a series of laser systems spanning from 657 nm to 1550 nm over several hundred meter distances.

Fiber-laser frequency combs with subhertz relative linewidths

October 15, 2006
Author(s)
William C. Swann, John J. McFerran, Ian R. Coddington, Nathan R. Newbury, Ingmar Hartl, Martin E. Fermann, Paul S. Westbrook, Jeffrey W. Nicholson, K Feder, Carston Langrock, Martin M. Fejer
We investigate the comb linewidths of self-referenced, fiber-laser-based frequency combs by measuring the heterodyne beat signal between two independent frequency combs that are phase locked to a common cw optical reference. We demonstrate that the optical

Fiber Frequency Combs: Development and Applications

September 19, 2006
Author(s)
Nathan R. Newbury, William C. Swann, Ian R. Coddington, John J. McFerran
The output of a femtosecond fiber laser provides a comb of lines in frequency space that can be phase-locked to either a microwave or optical reference to form a stable frequency comb. We discuss the basic configuration of fiber laser-based frequency combs

Elimination of pump-induced frequency jitter on fiber-laser frequency combs

July 1, 2006
Author(s)
John J. McFerran, William C. Swann, Brian R. Washburn, Nathan R. Newbury
Optical frequency combs generated by femtosecond fiber lasers typically exhibit significant frequency noise that causes broad optical linewidths, particularly in the comb wings and in the carrier-envelope offset frequency (fceo) signal. We show these broad

Reducing the linewidth of fiber-laser frequency combs

June 30, 2006
Author(s)
Nathan R. Newbury, John J. McFerran, William C. Swann
Fiber laser-based frequency combs typically exhibit broad optical linewidths, particularly in the wings. These broadened linewidths originate from white amplitude noise on the pump laser, which can be eliminated to achieve sub-Hz offset frequency