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arXiv · 1003.5925

Spin self-rephasing and very long coherence times in a trapped atomic ensemble

Christian Deutsch·Fernando Ramirez-Martinez·Clement Lacroûte·Friedemann Reinhard·Tobias Schneider·Jean-Noël Fuchs·Frédéric Piéchon·Franck Laloë·Jakob Reichel·Peter Rosenbusch
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Abstract

We perform Ramsey spectroscopy on the ground state of ultra-cold 87Rb atoms magnetically trapped on a chip in the Knudsen regime. Field inhomogeneities over the sample should limit the 1/e contrast decay time to about 3 s, while decay times of 58 s are actually observed. We explain this surprising result by a spin self-rephasing mechanism induced by the identical spin rotation effect originating from particle indistinguishability. We propose a theory of this synchronization mechanism and obtain good agreement with the experimental observations. The effect is general and susceptible to appear in other physical systems.

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Christian Deutsch, Fernando Ramirez-Martinez, Clement Lacroûte, Friedemann Reinhard, Tobias Schneider, Jean-Noël Fuchs, Frédéric Piéchon, Franck Laloë, Jakob Reichel, Peter Rosenbusch. 2010-05-28. Spin self-rephasing and very long coherence times in a trapped atomic ensemble. https://doi.org/10.1103/physrevlett.105.020401

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