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Bipartite entanglement measure based on covariances

Isabel Sainz Abascal·Gunnar Björk
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Abstract

We propose an entanglement measure for two qudits based on the covariances of a set of generators of the su(N) algebra. In particular, we represent this measure in terms of the mutually unbiased projectors for N prime. For pure states this measure quantify entanglement, we obtain an explicit expression which relates it to the concurrence hierarchy, specifically the I-concurrence and the 3-concurrence. For mixed states we propose a separability criterion.

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Isabel Sainz Abascal, Gunnar Björk. 2007-06-18. Bipartite entanglement measure based on covariances. https://arxiv.org/abs/quant-ph/0703249

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