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Entanglement cost of mixed states

G. Vidal·W. Dür·J. I. Cirac
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Abstract

We compute the entanglement cost of several families of bipartite mixed states, including arbitrary mixtures of two Bell states. This is achieved by developing a technique that allows us to ascertain the additivity of the entanglement of formation for any state supported on specific subspaces. As a side result, the proof of the irreversibility in asymptotic local manipulations of entanglement is extended to two-qubit systems.

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G. Vidal, W. Dür, J. I. Cirac. 2002-04-25. Entanglement cost of mixed states. https://doi.org/10.1103/physrevlett.89.027901

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