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Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)

Laser cooling and launching performance in a (1,1,1)-geometry atomic fountain

Elizabeth A. Donley, Thomas P. Heavner, J.W. O'Brien, Steven R. Jefferts, Filippo Levi

Published Jan 18, 2006• 5 citations
Publisher

Abstract

We have successfully cooled and launched cesium atoms in the (1,1,1) atomic fountain geometry at temperatures as low as 0.8 /spl mu/K. This corresponds to a root-mean-square thermal velocity of 0.7 cm/s, which is two times the photon recoil velocity of 0.35 cm/s. Factors that limit the final temperature are presented in detail.
DOI
10.1109/freq.2005.1573946

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We present a progress report on laser-cooled cesium atoms at NRC, work which was started a few years ago in order to realize a cesium fountain frequency standard. We selected an acceleration with two-dimensional moving molasses, which can increase both the force and the interaction time by a factor of /spl radic/2 over the more common 1-D molasses scheme. This configuration also allows for trapping and cooling of atoms while previously launched atoms are still moving in the clock section of the system. We report measurements on the number of atoms, temperature, friction coefficient and spring constant of our magneto-optical trap and 1-D molasses for various conditions.
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