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arXiv:cond-mat/0508439 · Physical Review Letters

Correlations and Counting Statistics of an Atom Laser

Anton Öttl, Stephan Ritter, Michael Köhl, Tilman Esslinger

Published Aug 26, 2005• 327 citations
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Abstract

We demonstrate time-resolved counting of single atoms extracted from a weakly interacting Bose-Einstein condensate of 87Rb atoms. The atoms are detected with a high-finesse optical cavity and single atom transits are identified. An atom laser beam is formed by continuously output coupling atoms from the Bose-Einstein condensate. We investigate the full counting statistics of this beam and measure its second order correlation function g((2))(tau) in a Hanbury Brown-Twiss type experiment. For the monoenergetic atom laser we observe a constant correlation function g((2))(tau)=1.00 +/- 0.01 and an atom number distribution close to a Poissonian statistics. A pseudothermal atomic beam shows a bunching behavior and a Bose distributed counting statistics.

DOI
10.1103/physrevlett.95.090404

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