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Search Publications by: William C. Swann (Fed)

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Displaying 126 - 150 of 159

Optical and microwave frequency synthesis with an integrated fiber frequency comb

June 5, 2006
Author(s)
Ingmar Hartl, Martin E. Fermann, William C. Swann, John J. McFerran, Ian R. Coddington, Qudsia Quraishi, Scott Diddams, Nathan R. Newbury, Carston Langrock, Martin M. Fejer, Paul S. Westbrook, Jeffrey W. Nicholson, K Feder
We demonstrate optical coherence over a broad spectral range of two independent fiber frequency combs. Additionally, we demonstrate microwave stability of better than 2x10 -14 in 1 second for an optically integrated fiber frequency comb.

Frequency-Resolved Coherent LIDAR using a Femtosecond Fiber Laser

May 21, 2006
Author(s)
William C. Swann, Nathan R. Newbury
We present a frequency comb-based, frequency-resolved coherent LIDAR (FReCL) that provides higher performance than that of conventional pulsed range/Doppler LIDARs, dramatically reduces local oscillator timing requirements, and compensates for path

Frequency-Resolved Coherent LIDAR using a Femtosecond Fiber Laser

March 15, 2006
Author(s)
William C. Swann, Nathan R. Newbury
We demonstrate a coherent lidar that uses a broadband femtosecond fiber laser as a source and resolves the returning heterodyne signal into N spectral channels by using an arrayed-waveguide grating. The data are processed incoherently to yield an N-times

Response Dynamics of the Frequency Comb Output from a Femtosecond Fiber Laser

December 26, 2005
Author(s)
Brian Washburn, William C. Swann, Nathan R. Newbury
The frequency comb from a mode-locked fiber laser can be stabilized through feedback to the pump power. An understanding of the mechanisms and bandwidth governing this feedback is of practical importance for frequency comb design and of basic interest

High-accuracy near infrared wavelength and frequency reference developments at NIST

September 23, 2005
Author(s)
William C. Swann, Sarah L. Gilbert, Brian Washburn, Nathan R. Newbury
NIST research on near infrared frequency and wavelength references is presented. A new high accuracy wavelength calibration transfer standard, SRM 2519a, based on molecular absorption lines of H13C14N is described. Research on optical frequency combs

Fiber Laser Frequency Combs and their Control

July 25, 2005
Author(s)
Nathan R. Newbury, Brian Washburn, William C. Swann, Jeffrey W. Nicholson, K Feder, Paul S. Westbrook
Fiber laser-based frequency combs can provide a comb of well-defined spectral lines across the near-infrared, including the telecommunication. We discuss these frequency combs with an emphasis on the mechanisms used to phase-lock the combs.

A variable repetition rate frequency comb for infrared frequency metrology

May 22, 2005
Author(s)
Brian Washburn, R W. Fox, William C. Swann, Nathan R. Newbury, Jeffrey W. Nicholson, K Feder, Paul S. Westbrook
A frequency comb generated by a variable repetition rate mode-locked fiber laser is presented. The spacing of the frequency comb can be scanned while one comb tooth is phase-locked to a stable RF source.

Accuracy limits for simple molecular absorption based wavelength references

September 1, 2004
Author(s)
William C. Swann, Sarah L. Gilbert
We present limitations on the characterization and use of molecular absorption lines for wavelength calibration purposes. These limits assume a Doppler and pressure-broadened absorption spectrum obtained by transmitting light through a simple gas cell

Absolute frequency measurements with a stabilized near-infrared optical frequency comb from a Cr:forsterite laser

May 16, 2004
Author(s)
Kristan L. Corwin, I Thomann, Tasshi Dennis, R W. Fox, William C. Swann, E. A. Curtis, C. W. Oates, G Wilpers, A Bartels, Sarah L. Gilbert, Leo W. Hollberg, Scott Diddams, Nathan R. Newbury, Jeffrey W. Nicholson, M. Yan
A Cr:forsterite laser-based frequency comb is stabilized simultaneously to two NIST frequency references. Methane lines from 1315 nm - 1330 nm are measured with ±2.3 MHz uncertainty. The pressure shifts are also evaluated.

Absolute frequency measurements with a stabilized near-infrared optical frequency comb from a Cr:forsterite laser

February 15, 2004
Author(s)
Kristan L. Corwin, I Thomann, A Bartels, Tasshi Dennis, W. Fox, William C. Swann, E. A. Curtis, C. W. Oates, G Wilpers, Sarah L. Gilbert, Leo W. Hollberg, Nathan R. Newbury, Scott A. Diddams, Jeffrey W. Nicholson, M. Yan
A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 υm. The

The NIST Traceable Reference Material Program for Wavelength Reference Absorption Cells

August 1, 2003
Author(s)
Timothy J. Drapela, Sarah L. Gilbert, William C. Swann, Chih-Ming Wang
A program is described by which commercially produced wavelength-calibration gas-absorption cells may be related to primary standards maintained by the National Institute of Standards and Technology (NIST) and Standard Reference Materials produced by NIST

Interleaved, Sampled Fiber Bragg Gratings for use in Hybrid Wavelength References

December 1, 2002
Author(s)
Michael W. Rabin, William C. Swann, Sarah L. Gilbert
We discuss the design and fabrication of interleaved, sampled fiber Bragg gratings (ISFBGs) for use in hybrid wavelength calibration references covering the 1300 nm to 1600 nm region. We demonstrate use of sampled phase masks (SPMs) to make sampled

Four-state measurement method for polarization dependent wavelength shift

September 1, 2002
Author(s)
William C. Swann, Shellee D. Dyer, Rex M. Craig
We present a novel four-state method for measuring the polarization dependent wavelength shift (PDW) of a fiber Bragg grating. We show that measurement of the grating's wavelength for only four different polarization states is sufficient to completely

Wavelength Calibration Standards for the WDM L-Band

September 1, 2001
Author(s)
William C. Swann, Sarah L. Gilbert
We describe National Institute of Standards and Technology research on wavelength standards for the optical communications L-band. We are developing a pair of transfer standards that can be used to calibrate the wavelength scale and scan linearity of

Wavelength References for 1300 nm and L-Band WDM

March 1, 2001
Author(s)
Tasshi Dennis, William C. Swann, Sarah L. Gilbert
We have surveyed potential references for 1300 nm and L-band wavelength calibration. We have developed a 1314 nm methane reference for our internal calibration and are developing a carbon-monoxide transfer standard for the 1560-1630 nm region.