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Experimental demonstration of a controlled-NOT wave-packet gate

B. DeMarco·A. Ben-Kish·D. Leibfried·V. Meyer·M. Rowe·B. M. Jelenković·W. M. Itano·J. Britton·C. Langer·T. Rosenband·D. J. Wineland
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Abstract

We report the experimental demonstration of a controlled-NOT (CNOT) quantum logic gate between motional and internal state qubits of a single ion where, as opposed to previously demonstrated gates, the conditional dynamics depends on the extent of the ion's wave-packet. Advantages of this CNOT gate over one demonstrated previously are its immunity from Stark shifts due to off-resonant couplings and the fact that an auxiliary internal level is not required. We characterize the gate logic through measurements of the post-gate ion state populations for both logic basis and superposition input states, and we demonstrate the gate coherence via an interferometric measurement.

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B. DeMarco, A. Ben-Kish, D. Leibfried, V. Meyer, M. Rowe, B. M. Jelenković, W. M. Itano, J. Britton, C. Langer, T. Rosenband, D. J. Wineland. 2002-08-28. Experimental demonstration of a controlled-NOT wave-packet gate. https://doi.org/10.1103/physrevlett.89.267901

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