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Entanglement and Collective Quantum Operations

Anthony Chefles·Claire R. Gilson·Stephen M. Barnett
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Abstract

We show how shared entanglement, together with classical communication and local quantum operations, can be used to perform an arbitrary collective quantum operation upon N spatially-separated qubits. A simple teleportation-based protocol for achieving this, which requires 2(N-1) ebits of shared, bipartite entanglement and 4(N-1) classical bits, is proposed. In terms of the total required entanglement, this protocol is shown to be optimal for even N in both the asymptotic limit and for `one-shot' applications.

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Anthony Chefles, Claire R. Gilson, Stephen M. Barnett. 2000-06-16. Entanglement and Collective Quantum Operations. https://doi.org/10.1016/s0375-9601(00)00461-8

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