Yb optical lattice clock

Since 1967, the SI second is defined on microwave frequency standards. However, atomic transitions in the optical domain show better stability and accuracy; this is the reason why the international metrology community is considering the possibility of a future redefinition of the second in terms of an optical frequency. In an ytterbium optical clock, the frequency of an ultra-stable laser is locked to the forbidden 1S0–3P0 transition of ytterbium prepared in an ultra-cold atom sample.

Our Yb clock has been characterized for the first time in 2016, when it has been measured respect to the Caesium fountain IT-CsF2. The measurement result was f(171Yb) = 518 295 836 590 863.59(31) Hz whit a relative uncertainty of 6e-16 limited by the Caesium fountain. This measurement is consistent and contributed to the recommended value for 171Yb as a secondary representation of the second in the International System of Units.

We are currently improving our setup for a new characterization aiming a relative uncertainty of 1e-17. For example we recently achieved high-resolution spectroscopy Fourier limited at 3 Hz level.

Our Yb clock participates in the EMPIR Project ROCIT and has contributed to the EMPIR Project OC18 the EMRP Project ITOC, the PRIN ACQUASIM, and the European projects ITN-FACT and SOC2.

Theses and positions available!

Contact us: m.pizzocaro[at]inrim.it, d.calonico[at]inrim.it

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