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Long-lived qubit memory using atomic ions

C. Langer·R. Ozeri·J. D. Jost·J. Chiaverini·B. DeMarco·A. Ben-Kish·R. B. Blakestad·J. Britton·D. B. Hume·W. M. Itano·D. Leibfried·R. Reichle·T. Rosenband·T. Schaetz·P. O. Schmidt·D. J. Wineland
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Abstract

We demonstrate experimentally a robust quantum memory using a magnetic-field-independent hyperfine transition in 9Be+ atomic ion qubits at a magnetic field B ~= 0.01194 T. We observe that the single physical qubit memory coherence time is greater than 10 seconds, an improvement of approximately five orders of magnitude from previous experiments with 9Be+. We also observe long coherence times of decoherence-free subspace logical qubits comprising two entangled physical qubits and discuss the merits of each type of qubit.

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C. Langer, R. Ozeri, J. D. Jost, J. Chiaverini, B. DeMarco, A. Ben-Kish, R. B. Blakestad, J. Britton, D. B. Hume, W. M. Itano, D. Leibfried, R. Reichle, T. Rosenband, T. Schaetz, P. O. Schmidt, D. J. Wineland. 2005-04-11. Long-lived qubit memory using atomic ions. https://doi.org/10.1103/physrevlett.95.060502

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