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arXiv · 1005.1922

Enhanced and reduced atom number fluctuations in a BEC splitter

Kenneth Maussang·G. Edward Marti·Tobias Schneider·Philipp Treutlein·Yun Li·Alice Sinatra·Romain Long·Jérôme Estève·Jakob Reichel
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Abstract

We measure atom number statistics after splitting a gas of ultracold 87Rb atoms in a purely magnetic double-well potential created on an atom chip. Well below the critical temperature for Bose-Einstein condensation T_c, we observe reduced fluctuations down to -4.9dB below the atom shot noise level. Fluctuations rise to more than +3.8dB close to T_c, before reaching the shot noise level for higher temperatures. We use two-mode and classical field simulations to model these results. This allows us to confirm that the super-shot noise fluctuations directly originate from quantum statistics.

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Kenneth Maussang, G. Edward Marti, Tobias Schneider, Philipp Treutlein, Yun Li, Alice Sinatra, Romain Long, Jérôme Estève, Jakob Reichel. 2010-05-11. Enhanced and reduced atom number fluctuations in a BEC splitter. https://doi.org/10.1103/physrevlett.105.080403

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