arXiv:1201.3544 · Physical Review Letters
Neutral Atom Frequency Reference in the Deep Ultraviolet with Fractional Uncertainty=5.7×10−15
John J. McFerran, L. Yi, Sinda Mejri, Sylvain Di Manno, W. Zhang, Jocelyne Guéna, Yann Le Coq, S. Bize
Abstract
We present an assessment of the ($6{s}^{2}$) $^{1}S_{0}\ensuremath{\leftrightarrow}(6s6p)^{3}P_{0}$ clock transition frequency in $^{199}\mathrm{Hg}$ with an uncertainty reduction of nearly 3 orders of magnitude and demonstrate an atomic quality factor $Q$ of $\ensuremath{\sim}{10}^{14}$. The $^{199}\mathrm{Hg}$ atoms are confined in a vertical lattice trap with light at the newly determined magic wavelength of $362.5697\ifmmode\pm\else\textpm\fi{}0.0011\text{ }\text{ }\mathrm{nm}$ and at a lattice depth of $20{E}_{R}$. The atoms are loaded from a single-stage magneto-optical trap with cooling light at 253.7 nm. The high $Q$ factor is obtained with an 80 ms Rabi pulse at 265.6 nm. We find the frequency of the clock transition to be $1\text{ }128\text{ }575\text{ }290\text{ }808\text{ }162.0\ifmmode\pm\else\textpm\fi{}6.4(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.3(\mathrm{stat})\text{ }\text{ }\mathrm{Hz}$ (i.e., with $\mathrm{\text{fractional uncertainty}}=5.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}15}$). Neither an atom number nor second order Zeeman dependence has yet been detected. Only three laser wavelengths are used for the cooling, lattice trapping, probing, and detection.