caesium clock

The main improvement in caesium clock accuracy has been achieved through the use of laser-cooled caesium atoms in laboratory clocks known as 'caesium fountains'.

That our provisionally trusty caesium clock should not, in certain well-defined senses, keep good time is indeed expected and well understood.

[38] Cutler L (June 2005) Fifty years of commercial caesium clocks. Metrologia 42:S90-S99.

The research has also led to the construction of extremely precise clocks that could become the future basis for a new standard of time, with more than hundred-fold greater precision than present-day caesium clocks, it said.

Now, these previous competitors can complement one another, and the technology of the optical clock leads to a considerable improvement of the established caesium clocks.