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Search Publications by: Kyle Beloy (Fed)

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Displaying 1 - 25 of 29

Clock-line-mediated Sisyphus Cooling

July 31, 2024
Author(s)
Jacob Siegel, Benjamin Hunt, Tanner Grogan, Youssef Hassan, Kyle Beloy, Roger Brown, Andrew Ludlow, Chun-Chia Chen, Kurt Gibble
We demonstrate sub-recoil Sisyphus cooling using the long-lived 3P0 clock state in alkaline-earthlike ytterbium. A 1388 -nm optical standing wave nearly resonant with the 3P0→3D1 transition creates a spatially periodic light shift of the 3P0 clock state

Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance

March 24, 2024
Author(s)
Jacob Siegel, Andrew Ludlow, Youssef Hassan, Kyle Beloy, Tanner Grogan, Chun-Chia Chen
We implement coherent delocalization as a tool for improving the two primary metrics of atomic clock performance: systematic uncertainty and instability. By decreasing atomic density with co- herent delocalization, we suppress cold-collision shifts and two

Trap-induced ac Zeeman shift of the thorium-229 nuclear clock frequency

March 8, 2023
Author(s)
Kyle Beloy
We examine the effect of a parasitic rf magnetic field, attributed to ion trapping, on the highly anticipated nuclear clock based on $^229}$Th$^3+}$ [C. J. Campbell \it et al.}, Phys.\ Rev.\ Lett.\ 108, 120802 (2012)]. The rf magnetic field induces an ac

High-accuracy optical clocks based on group 16-like highly charged ions

October 3, 2022
Author(s)
Saleh Allehabi, Samuel Brewer, Vladimir Dzuba, Victor Flambaum, Kyle Beloy
We identify laser-accessible transitions in group 16-like highly charged ions as candidates for high-accuracy optical clocks, including S-, Se-, and Te-like systems. For this class of ions, the ground 3PJ fi ne structure manifold exhibits irregular

Sub-recoil clock-transition laser cooling enabling shallow optical lattice clocks

September 8, 2022
Author(s)
Xiaogang Zhang, Kyle Beloy, Youssef Hassan, William McGrew, Chun-Chia Chen, Jacob Siegel, Tanner Grogan, Andrew Ludlow
Laser cooling is a key ingredient for quantum control of atomic systems in a variety of settings. In two-valence-electron atoms, two-stage Doppler cooling is typically used to bring atoms to the μK regime. Here, we implement a pulsed radial cooling scheme

Prospects of a Pb$^2+}$ ion clock

June 29, 2021
Author(s)
Kyle Beloy
We propose a high-performance atomic clock based on the 1.81 PHz transition between the ground and first-excited state of doubly ionized lead. Utilizing an even isotope of lead, both clock states have $I=J=F=0$, where $I$, $J$, and $F$ are the conventional

Frequency Ratio Measurements with 18-Digit Accuracy Using a Network of Optical Clocks

March 24, 2021
Author(s)
Kyle Beloy, Martha I. Bodine, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Jean-Daniel Deschenes, Scott Diddams, Robert J. Fasano, Tara Fortier, Youssef Hassan, David Hume, Dhruv Kedar, Colin J. Kennedy, Isaac Kader, Amanda Koepke, David Leibrandt, Holly Leopardi, Andrew Ludlow, Will McGrew, William Milner, Daniele Nicolodi, Eric Oelker, Tom Parker, John M. Robinson, Stefania Romisch, Stefan A. Schaeffer, Jeffrey Sherman, Laura Sinclair, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang
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 system. By exploiting higher resonance frequencies, optical atomic clocks

Measurement of the 27Al+ and 87Sr absolute optical frequencies

January 21, 2021
Author(s)
Holly Leopardi, Kyle Beloy, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Scott Diddams, Robert J. Fasano, Youssef S. Hassan, David B. Hume, Dhruv Kedar, Colin J. Kennedy, Isaac H. Khader, David R. Leibrandt, Andrew D. Ludlow, William F. McGrew, William R. Milner, Daniele Nicolodi, Eric Oelker, Thomas E. Parker, John M. Robinson, Stefania Romisch, Jeffrey A. Sherman, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang, Tara M. Fortier
We perform absolute measurement of the 27Al+ single-ion and 87Sr neutral lattice clock frequencies at the National Institute of Standards and Technology and JILA at the University of Colorado against a global ensemble of primary frequency standards. Over

Quadruply-ionized barium as a candidate for a high-accuracy optical clock

October 23, 2020
Author(s)
Kyle Beloy, Vladimir A. Dzuba, Samuel M. Brewer
We identify Ba$^4+}$ (Te-like) as a promising candidate for a high-accuracy optical clock. The lowest-lying electronic states are part of a $^3P_J$ fine structure manifold with anomalous energy ordering, being non-monotonic in $J$. We propose a clock based

Coherent Optical Clock Down-Conversion for Microwave Frequencies with 10-18 Instability

May 22, 2020
Author(s)
Takuma Nakamura, Josue Davila-Rodriguez, Holly Leopardi, Jeffrey Sherman, Tara Fortier, Xiaojun Xie, Joe C. Campbell, Will McGrew, Xiaogang Zhang, Youssef Hassan, Daniele Nicolodi, Kyle Beloy, Andrew Ludlow, Scott Diddams, Franklyn Quinlan
Optical atomic clocks are poised to redefine the SI second, thanks to stability and accuracy more than one hundred times better than the current microwave atomic clock standard. However, the best optical clocks have not seen their performance transferred

Modeling motional energy spectra and lattice light shifts in optical lattice clocks

May 8, 2020
Author(s)
Kyle Beloy, Will McGrew, Xiaogang Zhang, Daniele Nicolodi, Robert J. Fasano, Youssef Hassan, Roger Brown, Andrew Ludlow
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 and radial confinement relative to the lattice axis. Our model respects the

Measurements of 25 Mg + and 27 Al + magnetic constants for improved ion clock accuracy

July 15, 2019
Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan Clements, Chin-wen Chou, Kyle Beloy, Will McGrew, Xiaogang Zhang, Robert J. Fasano, Daniele Nicolodi, Holly Leopardi, Tara Fortier, Scott Diddams, Andrew Ludlow, David J. Wineland, David Leibrandt, David Hume
We have measured the quadratic Zeeman coefficient for the 3P0 excited electronic state in 27Al+, C2=-71.944(24) MHz/T2 and the hyperfine constant of the 25Mg+ 2S1/2 ground electronic state, Ahfs = -596 254 250.981(45) Hz, with improved uncertainties. Both

Towards the optical second: verifying optical clocks at the SI limit

April 11, 2019
Author(s)
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Holly Leopardi, Daniele Nicolodi, Kyle P. Beloy, Jian Yao, Jeffrey A. Sherman, Stefan A. Schaeffer, Joshua J. Savory, Stefania Romisch, Christopher W. Oates, Thomas E. Parker, Tara M. Fortier, Andrew D. Ludlow
The pursuit of ever more precise measures of time and frequency motivates redefinition of the second in terms of an optical atomic transition. To ensure continuity with the current definition, based on the microwave hyperfine transition in 133Cs, it is

First observation with global network of optical atomic clocks aimed for a dark matter detection

January 30, 2019
Author(s)
P. Wcislo, P. Ablewski, Kyle Beloy, S. Bilicki, M. Bober, Roger Brown, Robert J. Fasano, R. Ciurylo, H. Hachisu, T. Ido, J. Lodewyck, Andrew Ludlow, Will McGrew, P. Morzynski, Daniele Nicolodi, Marco Schioppo, M. Sekido, R. Le Targat, P. Wolf, Xiaogang Zhang, B. Zjawin, M. Zawada
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 fine- structure constant of essential parts of an optical atomic clock, i.e

Atomic clock performance beyond Earth’s gravitational limit

December 6, 2018
Author(s)
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Stefan A. Schaeffer, Kyle P. Beloy, Daniele Nicolodi, Roger C. Brown, N. Hinkley, G. Milani, Marco Schioppo, T. H. Yoon, Andrew D. Ludlow
The passage of time is tracked by counting oscillations of a suitable frequency reference (e.g., the number of revolutions of Earth around the sun or the number of swings of a pendulum of a grandfather clock). By referencing the oscillations arising from

Two-photon optical frequency reference with active AC Stark shift cancellation

July 30, 2018
Author(s)
Vladislav P. Gerginov, Kyle P. Beloy
An optical reference based on two-photon optical transition with AC stark shift cancellation is proposed. The reference uses two interrogating laser fields at different frequencies. Compared to conventional optical two-photon references, the new approach

A Faraday-shielded, DC Stark-free optical lattice clock

May 2, 2018
Author(s)
Kyle P. Beloy, Xiaogang Zhang, William F. McGrew, Nathan M. Hinkley, Tai H. Yoon, Daniele Nicolodi, Robert J. Fasano, Stefan A. Schaeffer, Roger C. Brown, Andrew D. Ludlow
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. Still, the effectiveness of the shielding must be experimentally assessed

Progress on Optical-clock-based Time Scale at NIST: Simulations and Preliminary Real-Data Analysis

April 20, 2018
Author(s)
Jian Yao, Jeffrey A. Sherman, Tara M. Fortier, Thomas E. Parker, Judah Levine, Joshua J. Savory, Stefania Romisch, William F. McGrew, Robert J. Fasano, Stefan A. Schaeffer, Kyle P. Beloy, Andrew D. Ludlow
This paper shows the recent NIST work on incorporating an optical clock into a time scale. We simulate a time scale composed of continuously-operating commercial hydrogen masers and an optical frequency standard that does not operate continuously as a

Hyper-Ramsey spectroscopy with probe laser intensity fluctuations

March 29, 2018
Author(s)
Kyle P. Beloy
We examine the influence of probe laser intensity fluctuations on hyper-Ramsey spectroscopy. We assume, as is appropriate for relevant cases of interest, that the probe laser intensity $I$ determines both the Rabi frequency $(\propto\sqrt)$ and the

Incorporating an Optical Clock into a Time Scale at NIST: Simulations and Preliminary Real-Data Analysis

March 29, 2018
Author(s)
Jian Yao, Jeffrey A. Sherman, Tara M. Fortier, Thomas E. Parker, Judah Levine, Joshua J. Savory, Stefania Romisch, William F. McGrew, Robert J. Fasano, Stefan A. Schaeffer, Kyle P. Beloy, Andrew D. Ludlow
This paper shows the recent NIST work on incorporating an optical clock into a time scale. We simulate a time scale composed of continuously-operating commercial hydrogen masers and an optical frequency standard that does not operate continuously as a

Hyperpolarizability and Operational Magic Wavelength in an Optical Lattice Clock

December 19, 2017
Author(s)
Roger C. Brown, Nate B. Phillips, Kyle P. Beloy, William F. McGrew, Marco Schioppo, Robert J. Fasano, Gianmaria Milani, Xiaogang Zhang, Nathan M. Hinkley, Holly F. Leopardi, T H. Yoon, Daniele Nicolodi, Tara M. Fortier, Andrew D. Ludlow
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 of frequency shifts that, if not properly controlled, may degrade clock

Hyperfine-mediated electric quadrupole shifts in Al+ and In+ ion clocks

April 6, 2017
Author(s)
Kyle P. Beloy, David R. Leibrandt, Wayne M. Itano
We evaluate the electric quadrupole moments of the 1S0 and 3P0 clock states of 27Al+ and 115In+. To capture all dominant contributions, our analysis extends through third order of perturbation theory and includes hyperfine coupling of the electrons to both

Ultra-stable optical clock with two cold-atom ensembles

January 1, 2017
Author(s)
Marco Schioppo, Roger Brown, Will McGrew, Nathan M. Hinkley, Robert J. Fasano, Kyle Beloy, Gianmaria Milani, Daniele Nicolodi, Jeffrey Sherman, Nate B. Phillips, Christopher W. Oates, Andrew Ludlow
Atomic clocks based on optical transitions are the most stable, and therefore precise, timekeepers available. These clocks operate by alternating intervals of atomic interrogation with ‘dead' time required for quantum state preparation and readout. This

Atomic Clock with 1x10 -18 Room-Temperature Blackbody Stark Uncertainty

December 31, 2014
Author(s)
Kyle P. Beloy, Nathan M. Hinkley, Nate B. Phillips, Jeffrey A. Sherman, Marco Schioppo, John H. Lehman, Ari D. Feldman, Leonard M. Hanssen, Christopher W. Oates, Andrew D. Ludlow
The Stark shift due to blackbody radiation (BBR) is a key factor limiting the performance of many atomic frequency standards, with the BBR environment inside the clock apparatus being difficult to characterize at a high level of precision. Here we