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Displaying 1 - 25 of 50

Cryogenic Sapphire Optical Reference Cavity with 1 x 10^-16 fractional instability

October 2, 2024
Author(s)
Jose Valencia, George Iskandr, Nicholas Nardelli, David Leibrandt, David Hume
The frequency stability of a laser locked to an optical reference cavity is fundamentally limited by thermal noise in the cavity length, caused by local thermal fluctuations of the strain and index of refraction of the cavity components. These fluctuations

Quantum state tracking and control of a single molecular ion in a thermal environment

August 1, 2024
Author(s)
Yu Liu, Julian Schmidt, Zhimin Liu, David Leibrandt, Dietrich Leibfried, Chin-wen Chou
Understanding molecular state evolution is central to many disciplines, including molecular dynamics, precision measurement, and molecule-based quantum technology. Details of this evolution are obscured when observing a statistical ensemble of molecules

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

Lifetime-Limited Interrogation of Two Independent 27Al+ Clocks using Correlation Spectroscopy

December 9, 2020
Author(s)
Ethan Clements, May E. Kim, Kaifeng Cui, Aaron M. Hankin, Samuel M. Brewer, Jose Valencia, Jwo-Sy Chen, Chin-wen Chou, David Leibrandt, David Hume
Laser decoherence limits the stability of optical clocks by broadening the observable resonance linewidths and adding noise during the dead time between clock probes. Correlation spectroscopy avoids these limitations by measuring correlated atomic

Quantum entanglement between an atom and a molecule

May 20, 2020
Author(s)
Yiheng Lin, David Leibrandt, Dietrich Leibfried, Chin-wen Chou
Expanding quantum control to a broad range of physical systems paves the way for advances in various aspects of science and technology, such as stringent tests of fundamental physics, quantum-enhanced sensors, and quantum information processing

Frequency-comb spectroscopy on pure quantum states of a single molecular ion

March 27, 2020
Author(s)
Chin-wen Chou, Alejandra L. Collopy, Christoph Kurz, Yiheng Lin, Michael E. Harding, Philipp N. Plessow, Tara M. Fortier, Scott A. Diddams, Dietrich G. Leibfried, David R. Leibrandt
Spectroscopy is a powerful tool for studying molecular properties and is commonly performed on large thermal ensembles of molecules that are perturbed by motional shifts and interactions with the environment and one another, resulting in convoluted spectra

Systematic uncertainty due to background-gas collisions in trapped-ion optical clocks

September 30, 2019
Author(s)
Aaron M. Hankin, Ethan Clements, Huang Yao, Samuel M. Brewer, Jwo-Sy Chen, Chin-wen Chou, David Hume, David Leibrandt
We describe a framework for calculating the frequency shift and uncertainty of trapped-ion optical atomic clocks caused by background-gas collisions, and apply this framework to an 27Al+ quantum-logic clock to enable a total fractional systematic

An 27 Al+ quantum-logic clock with systematic uncertainty below 10 -18

July 15, 2019
Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan Clements, Chin-wen Chou, David J. Wineland, David Hume, David Leibrandt
We describe an optical atomic clock based on quantum-logic spectroscopy of the 1S 0 3P 0 transition in 27Al + with a systematic uncertainty of 9.0 x 10-19 and a frequency stability of 1.2 X 10 -15/(T 1/2). A 25Mg + ion is simultaneously trapped with 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

Preparation and coherent manipulation of pure quantum states of a single molecular ion

May 11, 2017
Author(s)
Chin-Wen Chou, Christoph Kurz, David B. Hume, Philipp N. Plessow, David R. Leibrandt, Dietrich G. Leibfried
Laser cooling and trapping of atoms and atomic ions has led to breakthroughs in understanding of exotic phases of matter [1-3], development of exquisite sensors [4] and state-of-the-art atomic clocks [5]. For molecules, with their more complicated internal

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

Sympathetic Ground State Cooling and Time-dilation Shifts in an 27Al+ Optical Clock

February 3, 2017
Author(s)
Jwo-Sy Chen, Samuel M. Brewer, David B. Hume, Chin-Wen Chou, David J. Wineland, David R. Leibrandt
We report Raman sideband cooling of 25Mg+ to sympathetically cool the secular modes of motion in a 25Mg+-27Al+ two-ion pair to near the three-dimensional (3D) ground state. The evolution of the Fock state distributions during the cooling process is studied