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arXiv · quant-ph/9712045

Multi-Particle Entanglement Purification Protocols

M. Murao·M. B. Plenio·S. Popescu·V. Vedral·P. L. Knight
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Abstract

Purification schemes for multi-particle entangled states cannot be treated as straightforward extensions of those for two particles because of the lack of symmetry they possess. We propose purification protocols for a wide range of mixed entangled states of many particles. These are useful for understanding entanglement, and will be of practical significance in multi-user cryptographic schemes or distributed quantum computation and communication. We show that operating locally on multi-particle entangled states directly is more efficient than relying on two-particle purification.

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M. Murao, M. B. Plenio, S. Popescu, V. Vedral, P. L. Knight. 1997-12-19. Multi-Particle Entanglement Purification Protocols. https://doi.org/10.1103/physreva.57.r4075

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