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A bipartite separable ball and its applications

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 نشر من قبل Shu-Qian Shen
 تاريخ النشر 2015
  مجال البحث فيزياء
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In this paper, based on a matrix norm, we first present a ball of separable unnormalized states around the identity matrix for the bipartite quantum system, which is larger than the separable ball in Frobenius norm. Then the proposed ball is used to get not only simple sufficient conditions for the separability of pseudopure states and the states with strong positive partial transposes, but also a separable ball centered at the identity matrix for the multipartite quantum system.



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