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arXiv · 2304.10408

Towards the device-independent certification of a quantum memory

Pavel Sekatski·Jean-Daniel Bancal·Marie Ioannou·Mikael Afzelius·Nicolas Brunner
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Abstract

Quantum memories represent one of the main ingredients of future quantum communication networks. Their certification is therefore a key challenge. Here we develop efficient certification methods for quantum memories. Considering a device-independent approach, where no a priori characterisation of sources or measurement devices is required, we develop a robust self-testing method for quantum memories. We then illustrate the practical relevance of our technique in a relaxed scenario by certifying a fidelity of 0.87 in a recent solid-state ensemble quantum memory experiment. More generally, our methods apply for the characterisation of any device implementing a qubit identity quantum channel.

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Pavel Sekatski, Jean-Daniel Bancal, Marie Ioannou, Mikael Afzelius, Nicolas Brunner. 2023-04-20. Towards the device-independent certification of a quantum memory. https://doi.org/10.1103/physrevlett.131.170802

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