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Chris Oates


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

Ultra-stable optical clock with two cold-atom ensembles

Marco Schioppo, Roger C. Brown, William F. McGrew, Nathan M. Hinkley, Robert J. Fasano, Kyle P. Beloy, Gianmaria Milani, Daniele Nicolodi, Jeffrey A. Sherman, Nate B. Phillips, Christopher W. Oates, Andrew D. Ludlow
Atomic clocks based on optical transitions are the most stable, and therefore precise, timekeepers available. These clocks operate by alternating intervals of

Optical Lattice Clocks

Andrew D. Ludlow, Christopher W. Oates
Here we introduce and give a basic description of optical lattice clocks. We also briefly describe recent advances in these atomic frequency standards, looking

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

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
Created July 30, 2019