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arXiv · 1604.02202

Measurable genuine tripartite entanglement of ($2\otimes 2\otimes n$)-dimensional quantum states via only two simultaneous copies

Chang-shui Yu·Bao-qing Guo·Si-ren Yang
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Abstract

Usually, the three-tangle of a tripartite pure state of qubits can be directly measured with the simultaneous preparation of a not-less-than-four-fold copy of the state. We show that the exact genuine tripartite entanglement for ($2\otimes2\otimes n$)-dimensional pure quantum states can be measured in a similar manner, provided that only two simultaneous copies of the state are available. Lower bounds are also proposed for more convenient experimental operations. As an example, a comprehensive demonstration of the scheme is provided for the three-tangle of a three-qubit state.

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Chang-shui Yu, Bao-qing Guo, Si-ren Yang. 2016-04-08. Measurable genuine tripartite entanglement of ($2\otimes 2\otimes n$)-dimensional quantum states via only two simultaneous copies. https://doi.org/10.1103/physreva.93.042304

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