Atomic fountain clocks are becoming still more stable »

They are at present the most accurate clocks in the world: Caesium fountain clocks furnish the second accurate to 15 places after the decimal point. Until they reach this accuracy, caesium fountain clocks, however, need a certain measurement time. This time has now been considerably reduced with the aid of a new method developed at the Physikalisch-Technische Bundesanstalt (PTB) which makes the output frequency of the caesium fountains more stable. For excitation of the caesium atoms, the PTB physicists make use of a novel microwave source: they replace the oscillating quartz by a microwave oscillator which has been stabilized with the aid of a laser to such an extent that its noise becomes insignificant for fountain operation. For this purpose, techniques were applied which have originally been developed for optical atomic clocks which are regarded as the atomic clocks of the future. 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. The results are currently published in the journal Physical Review A.

Read Full Story at eurekalert.org »

169 Views Share Story 0 Comments Report