Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

David Hume (Fed)

Publications

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

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

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

Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan R. Clements, Chin-wen Chou, Kyle Beloy, William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Daniele Nicolodi, Holly Leopardi, Tara M. Fortier, Scott Diddams, Andrew D. Ludlow, David J. Wineland, David R. Leibrandt, David B. 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+

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

Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan R. Clements, Chin-wen Chou, David J. Wineland, David B. Hume, David R. Leibrandt
We describe an optical atomic clock based on quantum-logic spectroscopy of the 1S0 3P0 transition in 27Al+ with a systematic uncertainty of 9.0 x 10-19 and a
Created October 23, 2018, Updated June 15, 2021