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arXiv · 0804.2246

Novel Schemes for Directly Measuring Entanglement of General States

Jianming Cai·Wei Song
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Abstract

An intrinsic relation between maximally entangled states and entanglement measures is revealed, which plays a role in establishing connections for different entanglement quantifiers. We exploit the basic idea and propose a framework to construct schemes for directly measuring entanglement of general states. In particular, we demonstrate that rank-1 local factorizable projective measurements, which are achievable with only one copy of entangled state involved at a time in a sequential way, are sufficient to directly determine the concurrence of arbitrary two-qubit entangled state.

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Jianming Cai, Wei Song. 2008-11-05. Novel Schemes for Directly Measuring Entanglement of General States. https://doi.org/10.1103/physrevlett.101.190503

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