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Measurement of the 27Al+ and 87Sr absolute optical frequencies
Published
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
Abstract
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 an eight month period multiple measurements yielded the mean optical atomic transition frequencies nu_Al+ = 1,121,015,393,207,859.50(0.36) Hz and nu_Sr = 429,228,004,229,873.19(0.15) Hz, where the stated uncertainties are dominated by statistical noise and gaps in the observation interval ('dead-time' uncertainty).
Leopardi, H.
, Beloy, K.
, Bothwell, T.
, Brewer, S.
, Bromley, S.
, Chen, J.
, Diddams, S.
, Fasano, R.
, Hassan, Y.
, Hume, D.
, Kedar, D.
, Kennedy, C.
, Khader, I.
, Leibrandt, D.
, Ludlow, A.
, McGrew, W.
, Milner, W.
, Nicolodi, D.
, Oelker, E.
, Parker, T.
, Robinson, J.
, Romisch, S.
, Sherman, J.
, Sonderhouse, L.
, Swann, W.
, Yao, J.
, Ye, J.
, Zhang, X.
and Fortier, T.
(2021),
Measurement of the 27Al+ and 87Sr absolute optical frequencies, Metrologia, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=931072
(Accessed October 8, 2025)