We report vapor-cell magneto-optical trapping of Hg isotopes on the (1)S(0)-(3)P(1) intercombination transition. Six abundant isotopes, including four bosons and two fermions, were trapped. Hg is the heaviest nonradioactive atom trapped so far, which enables sensitive atomic searches for "new physics" beyond the standard model. We propose an accurate optical lattice clock based on Hg and evaluate its systematic accuracy to be better than 10;{-18}. Highly accurate and stable Hg-based clocks will provide a new avenue for the research of optical lattice clocks and the time variation of the fine-structure constant.

The first Earth-scale quantum sensor network based on optical atomic clocks is looking for dark matter candidates.

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The absolute frequency of the 87 Sr lattice clock transition was evaluated with an uncertainty of 1.1 × 10 −15 using a frequency link to the international atomic time (TAI). The frequency uncertainty of a hydrogen maser used as a transfer oscillator was reduced by homogeneously distributed intermittent measurement over a fiveday grid of TAI. Three sets of four or five days measurements as well as systematic uncertainty of the clock at 8.6 × 10 −17 have resulted in an absolute frequency of 87 Sr 1 S 0 − 3 P 0 clock transition to be 429 228 004 229 872.85 (47) Hz.

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