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arXiv · 1309.1203

Bounding the entanglement of N qubits with only four measurements

S. M. Hashemi Rafsanjani·C. J. Broadbent·J. H. Eberly
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Abstract

We introduce a new measure for the genuinely N-partite (all-party) entanglement of N-qubit states using the trace distance metric, and find an algebraic formula for the GHZ-diagonal states. We then use this formula to show how the all-party entanglement of experimentally produced GHZ states of an arbitrary number of qubits may be bounded with only four measurements.

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S. M. Hashemi Rafsanjani, C. J. Broadbent, J. H. Eberly. 2014-01-02. Bounding the entanglement of N qubits with only four measurements. https://doi.org/10.1103/physreva.88.062331

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