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Absolute frequency measurement of the 171Yb+ clock transition with a Kerr-lens mode-locked femtosecond laser

Joern Stenger·Christian Tamm·Nils Haverkamp·Stefan Weyers·Harald R. Telle
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Abstract

We have measured the frequency of the $6s^2S_{1/2} - 5d^2D_{3/2}$ electric-quadrupole transition of $^{171}$Yb$^+$ with a relative uncertainty of $1\times 10^{-14}$, $ν_{Yb}$ = 688 358 979 309 312 Hz $\pm$ 6 Hz. A femtosecond frequency comb generator was used to phase-coherently link the optical frequency derived from a single trapped ion to a cesium fountain controlled hydrogen maser. This measurement is one of the most accurate measurements of optical frequencies ever reported, and it represents a contribution to the development of optical clocks based on an $^{171}$Yb$^+$ ion standard.

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Joern Stenger, Christian Tamm, Nils Haverkamp, Stefan Weyers, Harald R. Telle. 2001-03-19. Absolute frequency measurement of the 171Yb+ clock transition with a Kerr-lens mode-locked femtosecond laser. https://doi.org/10.1364/ol.26.001589

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