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arXiv · 1103.2283

Extended coherence time on the clock transition of optically trapped Rubidium

G. Kleine Büning·J. Will·W. Ertmer·E. Rasel·J. Arlt·C. Klempt·F. Ramirez-Martinez·F. Piéchon·P. Rosenbusch
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Abstract

Optically trapped ensembles are of crucial importance for frequency measurements and quantum memories, but generally suffer from strong dephasing due to inhomogeneous density and light shifts. We demonstrate a drastic increase of the coherence time to 21 s on the magnetic field insensitive clock transition of Rb-87 by applying the recently discovered spin self-rephasing. This result confirms the general nature of this new mechanism and thus shows its applicability in atom clocks and quantum memories. A systematic investigation of all relevant frequency shifts and noise contributions yields a stability of 2.4E-11 x tau^(-1/2), where tau is the integration time in seconds. Based on a set of technical improvements, the presented frequency standard is predicted to rival the stability of microwave fountain clocks in a potentially much more compact setup.

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G. Kleine Büning, J. Will, W. Ertmer, E. Rasel, J. Arlt, C. Klempt, F. Ramirez-Martinez, F. Piéchon, P. Rosenbusch. 2011-03-11. Extended coherence time on the clock transition of optically trapped Rubidium. https://doi.org/10.1103/physrevlett.106.240801

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