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Cloning quantum entanglement in arbitrary dimensions

E. Karpov·P. Navez·N. J. Cerf
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Abstract

We have found a quantum cloning machine that optimally duplicates the entanglement of a pair of $d$-dimensional quantum systems. It maximizes the entanglement of formation contained in the two copies of any maximally-entangled input state, while preserving the separability of unentangled input states. Moreover, it cannot increase the entanglement of formation of all isotropic states. For large $d$, the entanglement of formation of each clone tends to one half the entanglement of the input state, which corresponds to a classical behavior. Finally, we investigate a local entanglement cloner, which yields entangled clones with one fourth the input entanglement in the large-$d$ limit.

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E. Karpov, P. Navez, N. J. Cerf. 2005-03-16. Cloning quantum entanglement in arbitrary dimensions. https://doi.org/10.1103/physreva.72.042314

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