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Multipartite entanglement for continuous variables: A quantum teleportation network

P. van Loock·Samuel L. Braunstein
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Abstract

We show that {\it one} single-mode squeezed state distributed among $N$ parties using linear optics suffices to produce a truly $N$-partite entangled state for any nonzero squeezing and arbitrarily many parties. From this $N$-partite entangled state, via quadrature measurements of $N-2$ modes, bipartite entanglement between any two of the $N$ parties can be `distilled', which enables quantum teleportation with an experimentally determinable fidelity better than could be achieved in any classical scheme.

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P. van Loock, Samuel L. Braunstein. 2000-06-19. Multipartite entanglement for continuous variables: A quantum teleportation network. https://doi.org/10.1103/physrevlett.84.3482

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