Applied Physics B

, Volume 89, Issue 2, pp 167–176

Optical-to-microwave frequency comparison with fractional uncertainty of 10-15

  • J.E. Stalnaker
  • S.A. Diddams
  • T.M. Fortier
  • K. Kim
  • L. Hollberg
  • J.C. Bergquist
  • W.M. Itano
  • M.J. Delany
  • L. Lorini
  • W.H. Oskay
  • T.P. Heavner
  • S.R. Jefferts
  • F. Levi
  • T.E. Parker
  • J. Shirley
Article

DOI: 10.1007/s00340-007-2762-z

Cite this article as:
Stalnaker, J., Diddams, S., Fortier, T. et al. Appl. Phys. B (2007) 89: 167. doi:10.1007/s00340-007-2762-z

Abstract

We report the technical aspects of the optical-to-microwave comparison for our recent measurements of the optical frequency of the mercury single-ion frequency standard in terms of the SI second as realized by the NIST-F1 cesium fountain clock. Over the course of six years, these measurements have resulted in a determination of the mercury single-ion frequency with a fractional uncertainty of less than 7×10-16, making it the most accurately measured optical frequency to date. In this paper, we focus on the details of the comparison techniques used in the experiment and discuss the uncertainties associated with the optical-to-microwave synthesis based on a femtosecond laser frequency comb. We also present our most recent results in the context of the previous measurements of the mercury single-ion frequency and arrive at a final determination of the mercury single-ion optical frequency: f(Hg+)=1 064 721 609 899 145.30(69) Hz.

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • J.E. Stalnaker
    • 1
  • S.A. Diddams
    • 1
  • T.M. Fortier
    • 1
    • 2
  • K. Kim
    • 1
  • L. Hollberg
    • 1
  • J.C. Bergquist
    • 1
  • W.M. Itano
    • 1
  • M.J. Delany
    • 1
  • L. Lorini
    • 1
  • W.H. Oskay
    • 1
  • T.P. Heavner
    • 1
  • S.R. Jefferts
    • 1
  • F. Levi
    • 1
  • T.E. Parker
    • 1
  • J. Shirley
    • 1
  1. 1.Time and Frequency Division, MS 847National Institute of Standards and TechnologyBoulderUSA
  2. 2.P-23 Physics Division, MS H803Los Alamos National LaboratoryLos AlamosUSA