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arXiv:quant-ph/0605250 · Physical Review Letters

Observable Entanglement Measure for Mixed Quantum States

Florian Mintert, Andreas Buchleitner

Published Apr 4, 2007• 169 citations
arXivHTMLPDF

Abstract

We quantify an unknown mixed quantum state's entanglement by suitable, local parity measurements on its twofold copy. The associated observable qualifies as a generalized entanglement witness.
DOI
10.1103/physrevlett.98.140505

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