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Search Publications by: Scott Diddams (Assoc)

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Displaying 201 - 225 of 320

Optical Microwave Frequency Stability: Some Constraints

July 25, 2005
Author(s)
Leo W. Hollberg, Scott A. Diddams, A Bartels, John J. McFerran, Eugene N. Ivanov, G Wilpers, Christopher W. Oates
Optical frequency references achieve the best frequency stability of any oscillators by taking advantage of high Q = υ 0/{Δ}υ optical resonances. These systems are beginning to run into fundamental and technical limitations which are discussed.

Spectroscopy of a single Al + ion via coupling to Be +

July 25, 2005
Author(s)
Till P. Rosenband, Piet Schmidt, Jeroen Koelemeij, Wayne M. Itano, Yohei Kobayashi, Tara M. Fortier, Scott A. Diddams, James C. Bergquist, David J. Wineland
We perform precision spectroscopy on 27Al + with the aid of a 9Be + ion. Using sympathetic cooling and quantum state transfer, we efficiently interrogate the 1S 0 – 3P 1 and 1S 0 – 3P 0 transitions.

High resolution spectroscopy with a femtosecond laser frequency comb

July 1, 2005
Author(s)
Vladislav Gerginov, C E. Tanner, Scott Diddams, A Bartels, Leo W. Hollberg
The output of a mode-locked femtosecond-laser is used for high resolution single-photon spectroscopy of ^133}Cs in an atomic beam. The laser is referenced directly to a stable RF signal from the NIST time-scale. By changing the laser's repetition rate, the

Femtosecond laser frequency combs: optical synthesizers for precision spectroscopy and frequency metrology

June 12, 2005
Author(s)
Scott A. Diddams, A Bartels, Tara M. Fortier, Eugene N. Ivanov, Kyoungsik Kim, John J. McFerran, Windell Oskay, G Wilpers, Christopher W. Oates, James C. Bergquist, Leo W. Hollberg, Vladislav Gerginov, C E. Tanner
A femtosecond laser frequency comb (FLFC) is the broadband (octave-spanning) evenly-spaced array of optical frequencies that is present in the output of a femtosecond mode-locked laser. Such frequency combs immediately found wide-spread use in optical

The Measurement of Optical Frequencies

June 7, 2005
Author(s)
Leo W. Hollberg, Scott A. Diddams, A Bartels, Tara M. Fortier, Kyoungsik Kim
Even the suggestion of counting optical frequencies in the visible (~ 500 THz) must have seemed ludicrous to many in the past, because traditional methods failed to work above about 100 GHz. Nonetheless, with some vision and new ideas a few researchers had

Stabilized frequency comb with a self-referenced femtosecond Cr:forsterite laser

May 27, 2005
Author(s)
Kyoungsik Kim, Brian R. Washburn, G Wilpers, C. W. Oates, Leo W. Hollberg, Nathan R. Newbury, Scott Diddams, Jeffrey W. Nicholson, M. Yan
The frequency comb of a Cr:forsterite femtosecond laser is stabilized using the f-to-2f self-referencing technique. The frequency noise of the comb components at 1064, 1314, and 1550nm differs significantly from the noise of f0.

Low noise synthesis of microwave signals from an optical source

May 26, 2005
Author(s)
John J. McFerran, Eugene N. Ivanov, A Bartels, G Wilpers, Christopher W. Oates, Scott A. Diddams, Leo W. Hollberg
We demonstrate the low noise synthesis of a harmonic comb of microwave frequencies using a femtosecond laser based synthesiser that is referenced to a cabity-stabilised laser. The residual phase noise is ~ -110dBc/Hz at 1 Hz from the 10 GHz harmonic. An

Ultra-high Stability Optical Frequency Standard Based on Laser-Cooled Neutral Calcium

May 22, 2005
Author(s)
G Wilpers, Christopher W. Oates, Scott A. Diddams, A Bartels, Windell Oskay, James C. Bergquist, Leo W. Hollberg
A beatnote between the Ca and Hg+ optical frequency standards via a mode-locked fs-laser frequency comb demonstrates the highest frequency stability measured to date. The high stability accelerates evaluation of the Ca standard's systematic shifts.

Optical frequency / wavelentgh references

April 25, 2005
Author(s)
Leo W. Hollberg, Christopher W. Oates, G Wilpers, C Hoyt, Zeb Barber, Scott A. Diddams, W Oskay, James C. Bergquist
Ideas for using visible light from atomic transitions for precision instrumentation and metrology go back at least to the 1800's. There are several good reasons to use optical frequencies, and with the scientific and technological advances of the last

International Comparisons of Femtosecond Laser Frequency Combs

April 1, 2005
Author(s)
Long-Sheng Ma, Zhiyi Bi, A Bartels, Lennart Robertsson, Massimo Zucco, Robert Windeler, G Wilpers, Christopher W. Oates, Leo W. Hollberg, Scott A. Diddams
Two types of international comparisons of femtosecond laser frequency combs have been performed in France and the USA. Five combs were involved in the comparisons. Three combs, of which two are transportable, employ nonlinear photonic crystal fiber (PCF)

Stabilized frequency comb with a self-referenced femtosecond Cr:forsterite laser

April 1, 2005
Author(s)
Kyoungsik Kim, Brian R. Washburn, G Wilpers, Christopher W. Oates, Leo W. Hollberg, Nathan R. Newbury, Scott A. Diddams, Jeffrey W. Nicholson, M. F. Yan
A frequency comb is generated with a Cr:forsterite femtosecond laser, spectrally broadened through a highly nonlinear optical fiber to span from 1.0 υm to 2.2 υm, and stabilized using the f-to-2f self-referencing technique. The repetition rate and the

Standards of time and frequency at the outset of the 21st century

November 19, 2004
Author(s)
Scott Diddams, James C. Bergquist, Steven R. Jefferts, Christopher W. Oates
In this paper we review state-of-the-art atomic time and frequency standards and discuss some of their uses in science and technology. After fifty years of development, microwave atomic clocks based on cesium have achieved fractional uncertainties below 1

The era of coherent optical frequency references

September 29, 2004
Author(s)
Leo W. Hollberg, Christopher W. Oates, Scott Diddams, G Wilpers, A Bartels, C Hoyt, Zeb Barber
The past four years have shown a dramatic improvement in the performance of optical frequency references and in the methods by which they are calibrated and utilized. These revolutionary changes result from better stabilized lasers that probe narrow

Infrared frequency comb for frequency metrology based on a tunable repetition rate fiber laser

September 1, 2004
Author(s)
Brian Washburn, Scott Diddams, Nathan R. Newbury, Jeffrey W. Nicholson, Feder Kenneth, Paul S. Westbrook, C. G. Jorgensen
A phase-locked, all-fiber supercontinuum source based on an ultrashort fiber ring laser with a tunable repetition frequency is presented. The supercontinuum output comprises a frequency comb with a spacing set by the laser repetition rate and an offset set

Precision tests of femtosecond laser optical frequency synthesizers

May 17, 2004
Author(s)
Long-Sheng Ma, Lennart Robertsson, Massimo Zucco, Zhiyi Bi, Robert Windeler, A Bartels, G Wilpers, Christopher W. Oates, Leo W. Hollberg, Scott Diddams
We compare the accuracy of femtosecond laser optical frequency synthesizers that employ microstructured fibers with those that directly generate a broadband output. No limitation of either system is found at fractional frequency levels of 1x10 -18.

A phase locked, fiber laser-based frequency comb: limit on optical linewidth

May 16, 2004
Author(s)
Brian Washburn, Scott Diddams, Nathan R. Newbury, Jeffrey W. Nicholson, M. Yan, C. G. Jorgensen
A phase-locked fiber laser-based supercontinuum source is presented. The linewidth of a single line of the IR frequency comb produced by fiber laser-based supercontinuum source is less than or equal to}6 kHz.