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arXiv · 2412.04479

Separability criteria based on realignment

Yu Lu·Zhong-Xi Shen·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

The detection of entanglement in a bipartite state is a crucial issue in quantum information science. Based on realignment of density matrices and the vectorization of the reduced density matrices, we introduce a new set of separability criteria. The proposed separability criteria can detect more entanglement than the previous separability criteria. Moreover, we provide new criteria for detecting the genuine tripartite entanglement and lower bounds for the concurrence and convex-roof extended negativity. The advantages of results are demonstrated through detailed examples.

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Yu Lu, Zhong-Xi Shen, Shao-Ming Fei, Zhi-Xi Wang. 2024-11-20. Separability criteria based on realignment. https://arxiv.org/abs/2412.04479

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