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Displaying 1 - 25 of 220

Early observations of macroscopic quantum jumps in single atoms

March 25, 2015
Author(s)
Wayne M. Itano, James C. Bergquist, David J. Wineland
The observation of intermittent fluorescence of a single atomic ion, a phenomenon better known as 'macroscopic quantum jumps,' was an important early scientific application of the three-dimensional rf quadrupole (Paul) trap. The prediction of the

Cavity-stabilized laser with acceleration sensitivity below 10 -12 /g -1

February 21, 2013
Author(s)
David R. Leibrandt, James C. Bergquist, Till P. Rosenband
We characterize the frequency-sensitivity of a cavity-stabilized laser to inertial forces and temperature fluctuations, and perform real-time feed-forward to correct for these sources of noise. We measure the sensitivity of the cavity to linear

Generation of Ultrastable microwaves via optical frequency division

June 26, 2011
Author(s)
Tara Fortier, Matthew S. Kirchner, Jennifer A. Taylor, James C. Bergquist, Yanyi Jiang, Andrew Ludlow, Christopher W. Oates, Till P. Rosenband, Scott Diddams, Franklyn Quinlan, Nathan D. Lemke
A frequency-stabilized femtosecond laser optical frequency comb serves as a source of microwave signals having very low close-to-carrier phase noise. Comparison of two independent systems shows combined absolute phase noise of -100 dBc/Hz at an offset of 1

Field-test of a robust, portable, frequency-stable laser

May 10, 2011
Author(s)
David R. Leibrandt, Michael J. Thorpe, James C. Bergquist, Till P. Rosenband
We operate a frequency-stable laser in a non-laboratory environment where the test platform is a passenger vehicle. We measure the acceleration experienced by the laser and actively correct for it to achieve a system acceleration sensitivity of df/f = 11(2

Spherical Reference Cavities for Ultra-Stable Lasers in Non-Laboratory Environments

February 14, 2011
Author(s)
David R. Leibrandt, Michael J. Thorpe, Mark Notcutt, Robert E. Drullinger, Till P. Rosenband, James C. Bergquist
We present an ultra-stable optical cavity design that is insensitive to both vibrations and orientation. The design is based on a spherical cavity spacer which is held rigidly at two points on a diameter of the sphere. Coupling of the support forces to the

Stylus ion trap for enhanced access and sensing

August 1, 2009
Author(s)
Robert Maiwald, Gerd Leuchs, Dietrich Leibfried, Joseph W. Britton, James C. Bergquist, David J. Wineland
We experimentally characterized a novel radio-frequency (rf) ion trap geometry formed by two concentric cylinders over a ground plane. These traps allow for optical and physical access over more than 2 pi solid angle reaching 91% and 96% of 4 respectively

Frequency Measurements of Al+ and Hg+ Optical Standards

June 8, 2009
Author(s)
Wayne M. Itano, James C. Bergquist, Till P. Rosenband, David J. Wineland, David Hume, Chin-wen Chou, Steven R. Jefferts, Thomas P. Heavner, Tom Parker, Scott Diddams, Tara Fortier
Frequency standards based on narrow optical transitions in 27Al+ and 199Hg+ ions have been developed at NIST. Both standards have absolute reproducibilities of a few parts in 10 17. This is about an order of magnitude better than the fractional uncertainty

Yb Optical Lattice Clock

November 23, 2008
Author(s)
Nathan D. Lemke, Andrew Ludlow, Zeb Barber, N Poli, C.W. Hoyt, Long-Sheng Ma, Jason Stalnaker, Christopher W. Oates, Leo Hollberg, James C. Bergquist, A. Brusch, Tara Fortier, Scott Diddams, Thomas P. Heavner, Steven R. Jefferts, Tom Parker
We describe the development and latest results of an optical lattice clock based on neutral Yb atoms, including investigations based on both even and odd isotopes. We report a fractional frequency uncertainty below 10 -15 for 171Yb.

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

Frequency evaluation of the doubly forbidden 1 S 0 - 3 P 0 transition in bosonic 174 Yb

May 6, 2008
Author(s)
Nicola Poli, Zeb Barber, Nathan D. Lemke, Christopher W. Oates, Tara Fortier, Scott Diddams, Leo W. Hollberg, James C. Bergquist, Anders Brusch, Steven R. Jefferts, Thomas P. Heavner, Tom Parker
We report an uncertainty evaluation of an optical lattice clock based on the 1S 0 – 3P 0 transition in the bosonic isotope 174Yb using magnetically induced spectroscopy. The uncertainty due to systematic effects has been reduced to less than 0.8Hz, which

Frequency ratio of Al + and Hg + single-ion optical clocks; metrology at the 17th decimal place

March 6, 2008
Author(s)
Till P. Rosenband, David Hume, P. O. Schmidt, Chin-Wen Chou, Anders Brusch, Luca Lorini, Windell Oskay, Robert E. Drullinger, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Nathan R. Newbury, W Swann, Wayne M. Itano, David J. Wineland, James C. Bergquist
We report the frequency ratio of the two most accurate and stable atomic clocks with a total fractional uncertainty of 5.2 X 10 -17 . This frequency ratio is the best-known physical constant that is not a simple integer. Repeated measurements during the