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arXiv · 2305.02002

Fundamental limits on quantum cloning from the no-signalling principle

Yanglin Hu·Marco Tomamichel
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Abstract

The no-cloning theorem is a cornerstone of quantum cryptography. Here we generalize and rederive in a unified framework various upper bounds on the maximum achievable fidelity of probabilistic and deterministic cloning machines. Building on ideas by Gisin [Phys.~Lett.~A, 1998], our result starts from the fact that remote state preparation is possible and the no-signalling principle holds. We apply our general theorem to several subsets of states that are of interest in quantum cryptography.

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Yanglin Hu, Marco Tomamichel. 2023-05-03. Fundamental limits on quantum cloning from the no-signalling principle. https://doi.org/10.1103/physreva.109.022221

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