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Frequency control of a lattice laser at 759 nm by referencing to Yb clock transition at 578 nm

We present the frequency control of a 759 nm laser as a lattice laser for an ytterbium (Yb) optical clock. The frequency stability and accuracy are transferred from the Yb optical clock via an optical frequency comb. Although the comb is fre-quency-stabilized on a rubidium microwave clock, the frequency instability of the 759 nm laser is evaluated at the 10 − 15 level at 1 s averaging time. The frequency of the 759 nm laser is controlled with an uncertainty within 1 Hz by referencing to the Yb clock transition. Such a frequency-controlled 759 nm laser is suitable for Yb optical clocks as the lattice laser. The technique of laser frequency control can be applied to other lasers in optical clocks.