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Xiaogang Zhang


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

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

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

P. Wcislo, P. Ablewski, Kyle P. Beloy, S. Bilicki, M. Bober, Roger C. Brown, Robert J. Fasano, R. Ciurylo, H. Hachisu, T. Ido, J. Lodewyck, Andrew D. Ludlow, William F. 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

Atomic clock performance beyond Earth’s gravitational limit

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

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

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

Hyperpolarizability and Operational Magic Wavelength in an Optical Lattice Clock

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
Created April 3, 2019