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High-fidelity teleportation beyond the no-cloning limit and entanglement swapping for continuous variables

Nobuyuki Takei·Hidehiro Yonezawa·Takao Aoki·Akira Furusawa
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Abstract

We experimentally demonstrate continuous-variable quantum teleportation beyond the no-cloning limit. We teleport a coherent state and achieve the fidelity of 0.70$\pm$0.02 that surpasses the no-cloning limit of 2/3. Surpassing the limit is necessary to transfer the nonclassicality of an input quantum state. By using our high-fidelity teleporter, we demonstrate entanglement swapping, namely teleportation of quantum entanglement, as an example of transfer of nonclassicality.

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Nobuyuki Takei, Hidehiro Yonezawa, Takao Aoki, Akira Furusawa. 2005-04-27. High-fidelity teleportation beyond the no-cloning limit and entanglement swapping for continuous variables. https://doi.org/10.1103/physrevlett.94.220502

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