Optical lattice clocks towards the redefinition of the second
نویسندگان
چکیده
Nowadays atomic optical lattice clocks can perform frequency measurements with a fractional uncertainty at the 10 level in few hours of measurement, outperforming the best caesium (Cs) standards operated in the world. Since the definition of the unit of time is based on Cs, a worldwide debate about the need to promote the redefinition of the second on a optical reference is under-way. At INRIM (Istituto Nazionale di Ricerca Metrologica) we developed an optical lattice clock based on ytterbium atoms and compared it against a Cs fountain. These results are an important contribution to the debate.
منابع مشابه
When should we change the definition of the second?
The microwave caesium (Cs) atomic clock has formed an enduring basis for the second in the International System of Units (SI) over the last few decades. The advent of laser cooling has underpinned the development of cold Cs fountain clocks, which now achieve frequency uncertainties of approximately 5×10(-16). Since 2000, optical atomic clock research has quickened considerably, and now challeng...
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