# Entanglement of Formation of an Arbitrary State of Two Qubits

@article{Wootters1998EntanglementOF,
title={Entanglement of Formation of an Arbitrary State of Two Qubits},
author={William K. Wootters},
journal={Physical Review Letters},
year={1998},
volume={80},
pages={2245-2248}
}
• W. Wootters
• Published 12 September 1997
• Physics
• Physical Review Letters
The entanglement of a pure state of a pair of quantum systems is defined as the entropy of either member of the pair. The entanglement of formation of a mixed state is defined as the minimum average entanglement of an ensemble of pure states that represents the given mixed state. An earlier paper [Phys. Rev. Lett. 78, 5022 (1997)] conjectured an explicit formula for the entanglement of formation of a pair of binary quantum objects (qubits) as a function of their density matrix, and proved the…
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