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Entanglement quantification through local observable correlations

Christian Kothe·Gunnar Björk
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Abstract

We present a significantly improved scheme of entanglement detection inspired by local uncertainty relations for a system consisting of two qubits. Developing the underlying idea of local uncertainty relations, namely correlations, we demonstrate that it's possible to define a measure which is invariant under local unitary transformations and which is based only on local measurements. It is quite simple to implement experimentally and it allows entanglement quantification in a certain range for mixed states and exactly for pure states, without first obtaining full knowledge (e.g. through tomography) of the state.

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Christian Kothe, Gunnar Björk. 2006-08-04. Entanglement quantification through local observable correlations. https://doi.org/10.1103/physreva.75.012336

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