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arXiv · 1012.3813

Long-lived periodic revivals of coherence in an interacting Bose-Einstein condensate

Mikhail Egorov·Russell P. Anderson·Valentin Ivannikov·Bogdan Opanchuk·Peter Drummond·Brenton V. Hall·Andrei I. Sidorov
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Abstract

We observe the coherence of an interacting two-component Bose-Einstein condensate (BEC) surviving for seconds in a trapped Ramsey interferometer. Mean-field driven collective oscillations of two components lead to periodic dephasing and rephasing of condensate wave functions with a slow decay of the interference fringe visibility. We apply spin echo synchronous with the self-rephasing of the condensate to reduce the influence of state-dependent atom losses, significantly enhancing the visibility up to 0.75 at the evolution time of 1.5s. Mean-field theory consistently predicts higher visibility than experimentally observed values. We quantify the effects of classical and quantum noise and infer a coherence time of 2.8 s for a trapped condensate of 5.5e4 interacting atoms.

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Mikhail Egorov, Russell P. Anderson, Valentin Ivannikov, Bogdan Opanchuk, Peter Drummond, Brenton V. Hall, Andrei I. Sidorov. 2011-08-23. Long-lived periodic revivals of coherence in an interacting Bose-Einstein condensate. https://doi.org/10.1103/physreva.84.021605

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