Optimal copying of entangled two-qubit states

Abstract

We investigate the problem of copying pure two-qubit states of a given degree of entanglement in an optimal way. Completely positive covariant quantum operations are constructed which maximize the fidelity of the output states with respect to two separable copies. These optimal copying processes hint at the intricate relationship between fundamental laws of quantum theory and entanglement.

arXiv comment13 pages, 7 figures

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Cited by in corpus (6)

• Quantum discord and its allies: a review
• Usefulness of classical communication for local cloning of entangled states
• Quantitative Treatment of Decoherence
• Universal covariant quantum cloning circuits for qubit entanglement manipulation
• Completely positive covariant two-qubit quantum processes and optimal quantum NOT operations for entangled qubit pairs
• Test of Common Sense in Quantum Copying Process