Mercury optical lattice clock exploiting a 2D-MOT: Lifetime of 3P0 state and frequency measurements.

Optical clocks have changed time and frequency metrology since the beginning of the 2000’s. The work was based on a mercury optical lattice clock. Mercury is a promising candidate for optical clocks thanks to its weak sensitivity to blackbody radiation shift. We took benefit of a magneto optical trap in two dimensions (2D-MOT) to pre-cool the mercury atoms before the interrogation phase. It allows us not only to trap much more atoms but also to improve the clock cycle by decreasing the total cycle time. These improvements made possible the lifetime measurement of the ³P₀ state and to participate to measurement campaigns at the European scale between different clocks located a few hundreds of kilometres apart. As a consequence, it was possible to measure for the first time the frequency ratio between mercury and Yb+ ion.

Clock, metrology, spectroscopy, optics, laser cooling, atomic physics

Full document: https://hal.archives-ouvertes.fr/tel-02501535