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arXiv · 1610.04735

Critical behaviour in the optimal generation of multipartite entanglement

M. G. M. Moreno·Fernando Parisio
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Abstract

Two systems whose correlations cannot be classically accounted for display the simplest instance of quantum entanglement. Although this two-party association has caused a revolution in the foundations and uses of quantum mechanics, genuine entanglement among several parties unveils a whole new class of phenomena and applications. In this work we suggest a way to prepare Dicke states from a tunable source of bipartite entanglement to investigate foundational issues. The scheme has the following distinctive features: (i) it relies on controlled information loss and {\it unentangled} measurements; (ii) irrespective of the source entanglement, whenever a Dicke state is produced, it is ideal; (iii) the optimal entanglement of the bipartite source undergoes a second-order-like transition depending on the parameters of the Dicke state to be produced. These properties lead to asymptotic results on the entanglement between any qubit belonging to a Dicke state and the remaining qubits.

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M. G. M. Moreno, Fernando Parisio. 2016-10-15. Critical behaviour in the optimal generation of multipartite entanglement. https://doi.org/10.1038/s41598-017-06299-5

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