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Sub-dekahertz spectroscopy of 199Hg+



J. C. Bergquist, R J. Rafac, B. A. Young, James A. Beall, Wayne M. Itano, David J. Wineland


Using a laser that is frequency locked to a Fabry-Perot etalon of high finesse and stability, we probe the 5d106s2S= (F=0, mf=0) 5d96s22d5/2 (F=2, mf=0) electric-quadrupole transition of a single laser-cooled 199Hg+ ion stored in a cryogenic radio-frequency ion trap. We observe Fourier-transoform limited linewidths as narrow as 6.7 Hz at 282 nm (1.06 x 1015 Hz). The functional form and estimated values of some of the frequency shifts of the 2S=2d5/2 "clock" transition (including the quadrupole shift), which have been calculated using a combination of measured atomic parameters and ab initio calculations, are given.
Proceedings Title
Laser Frequency Stabilization, Standards, Measurement, and Applications
Conference Dates
January 24-26, 2001
Conference Location
San Jose, CA, USA
Conference Title
SPIE - The International Society for Optical Engineering


atomic frequency standards, atomic spectroscopy, cooling and trapping, lasers' optical clocks


Bergquist, J. , Rafac, R. , Young, B. , Beall, J. , Itano, W. and Wineland, D. (2001), Sub-dekahertz spectroscopy of <sup>199</sup>Hg<sup>+</sup>, Laser Frequency Stabilization, Standards, Measurement, and Applications, San Jose, CA, USA (Accessed May 29, 2023)
Created September 20, 2001, Updated October 12, 2021