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Purification of two-qubit mixed states

Enric Jane
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Abstract

We find the necessary and sufficient condition under which two two-qubit mixed states can be purified into a pure maximally entangled state by local operations and classical communication. The optimal protocol for such transformation is obtained. This result leads to a necessary and sufficient condition for the exact purification of $n$ copies of a two-qubit state.

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Enric Jane. 2002-09-06. Purification of two-qubit mixed states. https://arxiv.org/abs/quant-ph/0205107

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