Absolute frequency measurements of the Hg+ and Ca optical clock transitions with a femtosecond laser.

  title={Absolute frequency measurements of the Hg+ and Ca optical clock transitions with a femtosecond laser.},
  author={Th. Udem and Scott A. Diddams and Kurt R. Vogel and C. W. Oates and Eleanor Curtis and W. D. Lee and Wayne M. Itano and R. E. Drullinger and James C. Bergquist and Leo Hollberg},
  journal={Physical review letters},
  volume={86 22},
The frequency comb created by a femtosecond mode-locked laser and a microstructured fiber is used to phase coherently measure the frequencies of both the Hg+ and Ca optical standards with respect to the SI second. We find the transition frequencies to be f(Hg) = 1 064 721 609 899 143(10) Hz and f(Ca) = 455 986 240 494 158(26) Hz, respectively. In addition to the unprecedented precision demonstrated here, this work is the precursor to all-optical atomic clocks based on the Hg+ and Ca standards… CONTINUE READING
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Publications referenced by this paper.
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  • A. Bartels, T. Dekorsy, H. Kurz
  • Lett. 24, 996
  • 1999
Highly Influential
2 Excerpts


  • S. Karshenboim
  • J. Phys. 78, 639
  • 2000
1 Excerpt


  • W. M. Itano, J. Res
  • Inst. Stand. Technol. 105, 829
  • 2000
2 Excerpts

The Hydrogen Atom

  • D. J. Wineland
  • 1989


  • A. I. Ferguson, J. N. Eckstein, T. W. Hänsch
  • Phys. 18, 257
  • 1979
1 Excerpt


  • H. Dehmelt
  • Am. Phys. Soc. 20, 60
  • 1975
1 Excerpt

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