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arXiv · 2103.07141

Detection of multipartite entanglement via quantum Fisher information

Yan Hong·Xianfei Qi·Ting Gao·Fengli Yan
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Abstract

In this paper, we focus on two different kinds of multipartite correlation, $k$-nonseparability and $k$-partite entanglement, both of which can describe the essential characteristics of multipartite entanglement. We propose effective methods to detect $k$-nonseparability and $k$-partite entanglement in terms of quantum Fisher information. We illustrate the significance of our results and show that they identify some $k$-nonseparability and $k$-partite entanglement that cannot be identified by known criteria by several concrete examples.

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Yan Hong, Xianfei Qi, Ting Gao, Fengli Yan. 2021-03-12. Detection of multipartite entanglement via quantum Fisher information. https://doi.org/10.1209/0295-5075%2F134%2F60006

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