732 citations · 2.1k across the 19 of their papers we have counts for
14 papers · 1 filter
Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance
Jacob Siegel, William McGrew, Youssef Hassan +5
We implement coherent delocalization as a tool for improving the two primary metrics of atomic clock performance: systematic uncertainty and instability. By decreasing atomic densi…
Sub-recoil clock-transition laser cooling enabling shallow optical lattice clocks
X. Zhang, K. Beloy, Y. S. Hassan +5
Laser cooling is a key ingredient for quantum control of atomic systems in a variety of settings. In divalent atoms, two-stage Doppler cooling is typically used to bring atoms to t…
Ytterbium nuclear-spin qubits in an optical tweezer array
Alec Jenkins, Joanna W. Lis, Aruku Senoo +2
We report on the realization of a fast, scalable, and high-fidelity qubit architecture, based on Yb atoms in an optical tweezer array. We demonstrate several attractive pro…
Optical coherence between atomic species at the second scale: improved clock comparisons via differential spectroscopy
May E. Kim, William F. McGrew, Nicholas V. Nardelli +9
Comparisons of high-accuracy optical atomic clocks \cite{Ludlow2015} are essential for precision tests of fundamental physics \cite{Safronova2018}, relativistic geodesy \cite{McGre…
Characterization and suppression of background light shifts in an optical lattice clock
R. J. Fasano, Y. J. Chen, W. F. McGrew +3
Experiments involving optical traps often require careful control of the ac Stark shifts induced by strong confining light fields. By carefully balancing light shifts between two a…
Frequency Ratio Measurements with 18-digit Accuracy Using a Network of Optical Clocks
Boulder Atomic Clock Optical Network, Collaboration, : +35
Atomic clocks occupy a unique position in measurement science, exhibiting higher accuracy than any other measurement standard and underpinning six out of seven base units in the SI…
Modeling motional energy spectra and lattice light shifts in optical lattice clocks
K. Beloy, W. F. McGrew, X. Zhang +5
We develop a model to describe the motional (i.e., external degree of freedom) energy spectra of atoms trapped in a one-dimensional optical lattice, taking into account both axial…
Measurements of Al and Mg magnetic constants for improved ion clock accuracy
S. M. Brewer, J. -S. Chen, K. Beloy +14
We have measured the quadratic Zeeman coefficient for the optical clock transition in Al, ~MHz/T, an…
Towards Adoption of an Optical Second: Verifying Optical Clocks at the SI Limit
W. F. McGrew, X. Zhang, H. Leopardi +13
The pursuit of ever more precise measures of time and frequency is likely to lead to the eventual redefinition of the second in terms of an optical atomic transition. To ensure con…
Atomic clock performance beyond the geodetic limit
W. F. McGrew, X. Zhang, R. J. Fasano +9
The passage of time is tracked by counting oscillations of a frequency reference, such as Earth's revolutions or swings of a pendulum. By referencing atomic transitions, frequency…
First observation with global network of optical atomic clocks aimed for a dark matter detection
P. Wcisło, P. Ablewski, K. Beloy +19
We report on the first earth-scale quantum sensor network based on optical atomic clocks aimed at dark matter (DM) detection. Exploiting differences in the susceptibilities to the…
Faraday-shielded, DC Stark-free optical lattice clock
K. Beloy, X. Zhang, W. F. McGrew +7
We demonstrate the absence of a DC Stark shift in an ytterbium optical lattice clock. Stray electric fields are suppressed through the introduction of an in-vacuum Faraday shield.…
Hyperpolarizability and operational magic wavelength in an optical lattice clock
R. C. Brown, N. B. Phillips, K. Beloy +11
Optical clocks benefit from tight atomic confinement enabling extended interrogation times as well as Doppler- and recoil-free operation. However, these benefits come at the cost o…
Ultra-stable optical clock with two cold-atom ensembles
M. Schioppo, R. C. Brown, W. F. McGrew +10
Atomic clocks based on optical transitions are the most stable, and therefore precise, timekeepers available. These clocks operate by alternating intervals of atomic interrogation…