Optimal estimation of two-qubit pure-state entanglement

Abstract

We present optimal measuring strategies for the estimation of the entanglement of unknown two-qubit pure states and of the degree of mixing of unknown single-qubit mixed states, of which N identical copies are available. The most general measuring strategies are considered in both situations, to conclude in the first case that a local, although collective, measurement suffices to estimate entanglement, a non-local property, optimally.

REVTEX, 9 pages, 1 figure

References in corpus (2)

• Entanglement of pure states for a single copy
• Minimal conditions for local pure-state entanglement manipulation

Cited by in corpus (23)

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