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arXiv · 2211.04868

A family of separability criteria and lower bounds of concurrence

Xian Shi·Yashuai Sun
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Abstract

The problem on detecting the entanglement of a bipartite state is significant in quantum information theory. In this article, we apply the Ky Fan norm to the revised realignment matrix of a bipartite state. Specifially, we consider a family of separable criteria for bipartite states, and present when the density matrix corresponds to a state is real, the criteria is equivalent to the enhanced realignment criterion. Moreover, we present analytical lower bounds of concurrence and the convex-roof extended negativity for arbitrary dimensional systems.

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Xian Shi, Yashuai Sun. 2022-11-09. A family of separability criteria and lower bounds of concurrence. https://arxiv.org/abs/2211.04868

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