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arXiv · 2007.10516

Catalyzed entanglement concentration of qubit pairs

Siddhartha Santra·Vladimir S. Malinovsky
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Abstract

We analytically obtain the maximum probability of converting a finite number of copies of an arbitrary two-qubit pure state to a single copy of a maximally entangled two-qubit pure state via entanglement assisted local operations and classical communications using a two-qubit catalyst state. We show that the optimal catalyst for this transformation is always more entangled than the initial state but any two-qubit state can act as a (non-optimal) catalyst. Interestingly, the entanglement of the optimal two-qubit catalyst state is shown to decrease with that of the initial state. Entanglement assisted strategies for obtaining multiple Bell states are discussed.

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Siddhartha Santra, Vladimir S. Malinovsky. 2020-07-20. Catalyzed entanglement concentration of qubit pairs. https://arxiv.org/abs/2007.10516

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