Open AccessDirect measurement of the frequency ratio for Hg and Yb optical lattice clocks and closure of the Hg/Yb/Sr loop
Author(s) -
Noriaki Ohmae,
Filippo Bregolin,
Nils Nemitz,
Hidetoshi Katori
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.391602
Subject(s) - ytterbium , strontium , optical lattice , lattice (music) , optics , materials science , mercury (programming language) , physics , atomic physics , laser , condensed matter physics , superfluidity , computer science , nuclear physics , acoustics , programming language
We performed the first direct measurement of the frequency ratio between a mercury ( 199 Hg) and an ytterbium ( 171 Yb) optical lattice clock to find ν Hg /ν Yb = 2.177 473 194 134 565 07(19) with the fractional uncertainty of 8.8 × 10 -17 . The ratio is in excellent agreement with expectations from the ratios ν Hg /ν Sr and ν Yb /ν Sr obtained previously in comparisons against a strontium ( 87 Sr) optical lattice clock. The completed closure (ν Hg /ν Yb )(ν Yb /ν Sr )(ν Sr /ν Hg ) - 1 = 0.4(1.3) × 10 -16 tests the frequency reproducibility of the optical lattice clocks beyond what is achievable in comparison against the current realization of the second in the International System of Units (SI).