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arXiv · 1207.3986

Persistency of entanglement and nonlocality in multipartite quantum systems

Nicolas Brunner·Tamas Vertesi
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Abstract

The behaviour under particle loss of entanglement and nonlocality is investigated in multipartite quantum systems. In particular, we define a notion of persistency of nonlocality, which leads to device-independent tests of persistent entanglement. We investigate the persistency of various classes of multipartite quantum states, exhibiting a variety of different behaviours. A particular attention is devoted to states featuring maximal persistency. Finally we discuss a link between the symmetry of a state and its persistency, illustrating the fact that too much symmetry reduces the strength of correlations among subsystems. These ideas also lead to a device-independent estimation of the asymmetry of a quantum state.

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Nicolas Brunner, Tamas Vertesi. 2012-07-17. Persistency of entanglement and nonlocality in multipartite quantum systems. https://doi.org/10.1103/physreva.86.042113

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