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Catalysis of entanglement manipulation for mixed states

J. Eisert·M. Wilkens
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Abstract

We consider entanglement-assisted remote quantum state manipulation of bi-partite mixed states. Several aspects are addressed: we present a class of mixed states of rank two that can be transformed into another class of mixed states under entanglement-assisted local operations with classical communication, but for which such a transformation is impossible without assistance. Furthermore, we demonstrate enhancement of the efficiency of purification protocols with the help of entanglement-assisted operations. Finally, transformations from one mixed state to mixed target states which are sufficiently close to the source state are contrasted to similar transformations in the pure-state case.

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J. Eisert, M. Wilkens. 2000-05-22. Catalysis of entanglement manipulation for mixed states. https://doi.org/10.1103/physrevlett.85.437

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