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Search Publications by: Tara Fortier (Fed)

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Displaying 76 - 92 of 92

A Low-Threshold Self-Referenced Ti:Sapphire Optical Frequency Comb

October 2, 2006
Author(s)
Matthew S. Kirchner, Tara M. Fortier, A Bartels, Scott A. Diddams
We demonstrate an octave-spanning, self-referenced optical frequency comb produced with a high repetition rate (frep=585 MHz) femtosecond Ti:Sapphire laser that requires less that 1 W of 532 nm pump power. The frequency comb was stabilized to a CW laser as

A single-atom optical clock with high accuracy

July 14, 2006
Author(s)
Windell Oskay, Scott A. Diddams, Elizabeth A. Donley, Tara M. Fortier, Thomas P. Heavner, Leo W. Hollberg, Wayne M. Itano, Steven R. Jefferts, M J. Jensen, Kyoungsik Kim, F Levi, Thomas E. Parker, James C. Bergquist
For the past fifty years, atomic frequency standards based on the cesium ground-state hyperfine splitting have been the most accurate timepieces in the world. One of the most accurate, current-generation, cesium standards is the NIST-F1 fountain, which has

Absolute Optical Frequency Measurements with a Fractional Uncertainty at 1 x 10 -15

June 5, 2006
Author(s)
Jason Stalnaker, Scott A. Diddams, Leo W. Hollberg, Kyoungsik Kim, Elizabeth A. Donley, Thomas P. Heavner, Steven R. Jefferts, Filippo Levi, Thomas E. Parker, James C. Bergquist, Wayne M. Itano, Marie J. Jensen, Luca Lorini, Windell Oskay, Tara M. Fortier, J Torgerson
We report the technical details specific to our recent measurements of the optical frequency of the mercury single-ion clock in terms of the SI second as realized by the NIST-F1 cesium fountain clock. In these measurements the total fractional uncertainty

Stability measurements of the Ca and Yb Optical Frequency Standards

June 5, 2006
Author(s)
Christopher W. Oates, C Hoyt, Yann Le Coq, Zeb Barber, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Leo W. Hollberg
In this paper we describe two types of optical atomic clocks. The first is based on freely expanding calcium atoms and is optimized for experimental simplicity and high stability. The second is based on Yb atoms confined to an optical lattice that is

Phase-stabilized ultrafast lasers signal new era in measurement and research

May 15, 2006
Author(s)
Tara M. Fortier, A Bartels, Scott A. Diddams
The development of short-pulsed lasers has progressed steadily over the past 30 years. In the search for better techniques and materials to generate shorter and shorter pulses, the 1990?s witnessed the arrival of Kerr-lens mode-locked Ti:sapphire lasers as

Phase-Stabilized Ultrafast Lasers Signal New Era Measurement and Research

May 1, 2006
Author(s)
Tara M. Fortier, A Bartels, Scott A. Diddams
The development of short pulsed lasers has progressed steadily over the past 30 years. In the search for better techniques and materials to generate shorter and shorter pulses, the 1990's witnessed the arrival of Kerr-lens mode locked Ti:sapphire lasers as

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.

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
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