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arXiv:quant-ph/0609019 · AIP conference proceedings

Producing and Detecting Correlated Atoms

Christoph Ira Westbrook, M. Schellekens, A. Perrin, Valentina Krachmalnicoff, J. Viana Gomes, Jean-Baptiste Trebbia, Jérôme Estève, Hong Chang, Isabelle Bouchoule, Denis Boiron, Alain Aspect, T. Jeltes, J. McNamara, W. Hogervorst, W. Vassen

Published Jan 1, 2006• 2 citations

Abstract

We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions. We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four‐wave mixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

DOI: 10.1063/1.2400648

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We study atom scattering from two colliding Bose-Einstein condensates using a position sensitive, time resolved, single atom detector. In analogy to quantum optics, the process can also be thought of as spontaneous, degenerate four wave mixing of de Broglie waves. We find a clear correlation between atoms with opposite momenta, demonstrating pair production in the scattering process. We also observe a Hanbury Brown and Twiss correlation for collinear momenta, which permits an independent measurement of the size of the pair production source and thus the size of the spatial mode. The back to back pairs occupy very nearly two oppositely directed spatial modes, a promising feature for future quantum optics experiments.

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