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arXiv · 2210.11447

Robust Quantum Memory in a Trapped-Ion Quantum Network Node

P. Drmota·D. Main·D. P. Nadlinger·B. C. Nichol·M. A. Weber·E. M. Ainley·A. Agrawal·R. Srinivas·G. Araneda·C. J. Ballance·D. M. Lucas
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Abstract

We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in Sr-88 is transferred to Ca-43 with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with a second photon, without affecting the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ~70 times slower on the memory qubit. Dynamical decoupling further extends the storage duration; we measure an ion-photon entanglement fidelity of 0.81(4) after 10s.

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P. Drmota, D. Main, D. P. Nadlinger, B. C. Nichol, M. A. Weber, E. M. Ainley, A. Agrawal, R. Srinivas, G. Araneda, C. J. Ballance, D. M. Lucas. 2022-10-20. Robust Quantum Memory in a Trapped-Ion Quantum Network Node. https://doi.org/10.1103/physrevlett.130.090803

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