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Displaying 1 - 25 of 48

Characterization and suppression of background light shifts in an optical lattice clock

April 8, 2021
Author(s)
Robert J. Fasano, Yun Jhih Chen, Will McGrew, Wesley J. Brand, Richard W. Fox, Andrew Ludlow
Experiments involving optical traps often require precise control of the ac Stark shifts induced by strong confining light fields. By carefully balancing light shifts between two atomic states of interest, optical traps at the magic wavelength have been

Ramsey-Borde Matter-Wave Interferometry for Laser Frequency Stabilization at 10 -16 Frequency Instability and Below

August 13, 2019
Author(s)
Judith B. Olson, Todd Sheerin, Holly Leopardi, Roger C. Brown, Richard W. Fox, Rick Stoner, Tara M. Fortier, Christopher W. Oates, Andrew D. Ludlow
We demonstrate Ramsey-Borde (RB) atom interferometry for high performance laser stabilization with fractional frequency instability −16 for timescales between 10 and 1000s. The RB spectroscopy laser interrogates two counterpropagating 40Ca beams on the 1S

Photonic-Chip Supercontinuum with Tailored Spectra for Counting Optical Frequencies

July 24, 2017
Author(s)
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Judith B. Olson, Richard W. Fox, Roger C. Brown, Andrew D. Ludlow, Qing Li, Daron A. Westly, Tara M. Fortier, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
Supercontinuum generation using chip-integrated photonic waveguides is a powerful approach for spectrally broadening pulsed laser sources with very low pulse energies and compact form factors. When pumped with a mode-locked laser frequency comb, these

A high stability optical frequency reference based on thermal calcium atoms

May 24, 2012
Author(s)
Richard W. Fox, Jeffrey Sherman, W. Douglas, Judith B. Olson, Andrew Ludlow, Christopher W. Oates
Here we report an imprecision below 10 -14 with a simple, compact optical frequency standard based upon thermal calcium atoms. Using a Ramsey-Borde spectrometer we excite features with linewidths

Blackbody effects in the Yb optical lattice clock

May 24, 2012
Author(s)
Andrew D. Ludlow, Jeffrey A. Sherman, Nathan D. Lemke, Kyle P. Beloy, Nathan M. Hinkley, M. Pizzocaro, Richard W. Fox, Christopher W. Oates
We report a high accuracy measurement of the differential static polarizability for the clock transition in a Yb lattice clock, a key parameter for determining the blackbody BBR) shift of this transition. We further report efforts to determine the 6s5d3D1

High-Accuracy Measurement of Atomic Polarizability in an Optical Lattice Clock

April 13, 2012
Author(s)
Jeffrey A. Sherman, Nathan D. Lemke, Nathan M. Hinkley, M. Pizzocaro, Richard W. Fox, Andrew D. Ludlow, Christopher W. Oates
Presently, the Stark effect contributes the largest source of uncertainty in a ytterbium optical atomic clock through blackbody radiation. By employing an ultracold, trapped atomic ensemble and high stability optical clock, we characterize the quadratic

Improving the stability and accuracy of the Yb optical lattice clock

July 31, 2011
Author(s)
Andrew D. Ludlow, Yanyi Jiang, Nathan D. Lemke, Jeffrey A. Sherman, J. von Stecher, Richard W. Fox, Long-Sheng Ma, A.M. Rey, Christopher W. Oates
We report results for improving the stability and uncertainty of the NIST $^{171}$Yb lattice clock. The stability improvements derive from a significant reduction of the optical Dick effect, while the uncertainty improvements focus on improved

Making optical atomic clocks more stable with 10 -16 level laser stabilization

January 23, 2011
Author(s)
Andrew D. Ludlow, Yanyi Jiang, Nathan D. Lemke, Richard W. Fox, Jeffrey A. Sherman, Long-Sheng Ma, Christopher W. Oates
The superb precision of an atomic clock is derived from its stability. Atomic clocks based on optical (rather than microwave) frequencies are attractive because of their potential for high stability, which scales with operational frequency. Nevertheless

Temperature analysis of low-expansion Fabry-Perot cavities

August 17, 2009
Author(s)
Richard W. Fox
A model of the temperature response of low-expansion glass Fabry-Perot cavities that includes structural distortion at the contacted mirrors compares well to frequency measurements of different cavities built with the same spacer. The path elongation at

Albedo Measurements and Optical Sizing of Single Aerosol Particles

July 31, 2008
Author(s)
Todd J. Sanford, Daniel Murphy, David S. Thomson, Richard W. Fox
Aerosols play an important role in global climate change by their interactions with incoming solar radiation and outgoing longwave radiation from the planetary surface. The climate effects of aerosols depend on their scattering and absorption properties

Fabry-Perot temperature dependence and surface-mounted optical cavities

June 2, 2008
Author(s)
Richard W. Fox
Factors that contribute to the resonance temperature dependence of low-expansion optical cavities are discussed, including deformation at the cavity ends due to different coefficients of thermal expansion (CTE) of the spacer, optically-contacted mirror

Wavelength References for Interferometry in Air

December 12, 2005
Author(s)
Richard W. Fox, Brian R. Washburn, Nathan R. Newbury, Leo W. Hollberg
Interferometer sources with multiple known wavelengths can be provided by tunable lasers and calibrated optical reference cavities. The mode wavelengths are known by measuring a laser¿s frequency while locked to the mode in vacuum during a calibration step

Wavelength References for Optical Interferometry

June 12, 2005
Author(s)
Richard W. Fox, Leo W. Hollberg
We are exploring air wavelength references useful for interferometry. Femtosecond comb frequency measurements determine mode wavelengths of a stable optical cavity in vacuum, and subsequently a tunable laser is locked to the modes in air.