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Convex-roof extended negativity as an entanglement measure for bipartite quantum systems

Soojoon Lee·Dong Pyo Chi·Sung Dahm Oh·Jaewan Kim
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Abstract

We extend the concept of the negativity, a good measure of entanglement for bipartite pure states, to mixed states by means of the convex-roof extension. We show that the measure does not increase under local quantum operations and classical communication, and derive explicit formulae for the entanglement measure of isotropic states and Werner states, applying the formalism presented by Vollbrecht and Werner [Phys. Rev. A {\bf 64}, 062307 (2001)].

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Soojoon Lee, Dong Pyo Chi, Sung Dahm Oh, Jaewan Kim. 2003-10-04. Convex-roof extended negativity as an entanglement measure for bipartite quantum systems. https://doi.org/10.1103/physreva.68.062304

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