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arXiv · 1603.02758

Strong monogamy of multi-party quantum entanglement for partially coherently superposed states

Jeong San Kim
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Abstract

We provide an evidence for the validity of strong monogamy inequality of multi-party quantum entanglement using square of convex-roof extended negativity(SCREN). We first consider a large class of multi-qudit mixed state that are in a partially coherent superposition of a generalized W-class state and the vacuum, and provide some useful properties about this class of states. We show that monogamy inequality of multi-qudit entanglement in terms of SCREN holds for this class of states. We further show that SCREN strong monogamy inequality of multi-qudit entanglement also holds for this class of states. Thus SCREN is a good alternative to characterize the monogamous and strongly monogamous properties of multi-qudit entanglement.

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Jeong San Kim. 2016-03-09. Strong monogamy of multi-party quantum entanglement for partially coherently superposed states. https://doi.org/10.1103/physreva.93.032331

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