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arXiv · 2102.02709

Semi-device-independent certification of entanglement in superdense coding

George Moreno·Ranieri Nery·Carlos de Gois·Rafael Rabelo·Rafael Chaves
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Abstract

Superdense coding is a paradigmatic protocol in quantum information science, employing a quantum communication channel to send classical information more efficiently. As we show here, it can be understood as a particular case of a prepare and measure experiment, a scenario that has attracted growing attention for its fundamental and practical applications. Formulating superdense coding as a prepare and measure scenario allows us to provide a semi-device-independent witness of entanglement that significantly improves over previous tests. Furthermore, we also show how to adapt our results into self-testing of maximally entangled states and also provide a semidefinite program formulation allowing to efficiently optimize, for any shared quantum state, the probability of success in the superdense coding protocol.

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George Moreno, Ranieri Nery, Carlos de Gois, Rafael Rabelo, Rafael Chaves. 2021-03-22. Semi-device-independent certification of entanglement in superdense coding. https://doi.org/10.1103/physreva.103.022426

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