Skip to Main content Skip to Navigation

Amélioration de l'exactitude d'une horloge atomique compacte à jet de césium pompé optiquement

Abstract : The aim of this work is to study and compare several measurement methods of the Ramsey cavity phase difference in an optically pumped cesium beam atomic clock.
The first part of this report concerns the study and the realization of a compact atomic clock with two cesium beams. The small resonator and especially the Ramsey cavity, which is the heart of the machine, are described. The Ramsey cavity is a microwave cavity, carefully tuned at 9.192 GHz with two separated interaction regions. The influence of the cavity features and of the adjustement parameters on the clock operation is pointed out, especially the effect of the residual phase difference between the two interaction regions.
Then the theoretical study of the phase difference influence on the Ramsey pattern is reported allowing us to establish several measurement methods of this cavity default.
The third part is devoted to the residual phase difference measurements. The classical method, called beam reversal method, always used in all the primary frequency standards is shown to be the more reliable and the more accurate in our case. A second method in the case of compact atomic clocks leads us to deduce the cavity phase difference through clock frequency measurement at different operationnal conditions. This method is not easy to implement and its limit is shown.
Finally, all the frequency shifts are experimentally studied and measured in order to evaluate the clock. The performances of the small optically pumped cesium beam atomic clock are pointed out. The frequency shift due to the cavity phase difference is still the accuracy limiting effect. However the second method of measurement demonstrates a clock frequency accuracy limitation better than 10-12.
Complete list of metadatas
Contributor : Luc Chassagne <>
Submitted on : Tuesday, May 21, 2002 - 3:33:50 PM
Last modification on : Monday, October 19, 2020 - 11:06:42 AM
Long-term archiving on: : Friday, April 2, 2010 - 6:03:53 PM


  • HAL Id : tel-00001358, version 1



Luc Chassagne. Amélioration de l'exactitude d'une horloge atomique compacte à jet de césium pompé optiquement. Physique Atomique [physics.atom-ph]. Université Paris Sud - Paris XI, 2000. Français. ⟨tel-00001358⟩



Record views


Files downloads