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arXiv · 0803.1232

Linear optical scheme to demonstrate genuine multipartite entanglement for single-particle W states

Hyunchul Nha
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Abstract

We consider the method of entanglement witness operator to verify genuine multipartite entanglement for single-particle W states involving N parties. In particular, linear optical schemes using photo detectors and beam splitters are proposed to implement two different types of witness operator in experiment. The first scheme that requires only a single measurement setting is shown to detect genuine multipartite entanglement for the overall efficiency beyond 1-1/N. On the other hand, the second scheme with N+1 measurement settings achieves success at a significantly lowered efficiency than 1-1/N.

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Hyunchul Nha. 2008-03-08. Linear optical scheme to demonstrate genuine multipartite entanglement for single-particle W states. https://doi.org/10.1103/physreva.77.062328

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