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Multipartite Asymmetric Quantum Cloning

S. Iblisdir·A. Acin·N. Gisin·J. Fiurasek·R. Filip·N. J. Cerf
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Abstract

We investigate the optimal distribution of quantum information over multipartite systems in asymmetric settings. We introduce cloning transformations that take $N$ identical replicas of a pure state in any dimension as input, and yield a collection of clones with non-identical fidelities. As an example, if the clones are partitioned into a set of $M_A$ clones with fidelity $F^A$ and another set of $M_B$ clones with fidelity $F^B$, the trade-off between these fidelities is analyzed, and particular cases of optimal $N \to M_A+M_B$ cloning machines are exhibited. We also present an optimal $1 \to 1+1+1$ cloning machine, which is the first known example of a tripartite fully asymmetric cloner. Finally, it is shown how these cloning machines can be optically realized.

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S. Iblisdir, A. Acin, N. Gisin, J. Fiurasek, R. Filip, N. J. Cerf. 2004-11-24. Multipartite Asymmetric Quantum Cloning. https://doi.org/10.1103/physreva.72.042328

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