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Constructing optimal entanglement witnesses. II

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 نشر من قبل Dariusz Chruscinski
 تاريخ النشر 2010
  مجال البحث فيزياء
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We provide a class of optimal nondecomposable entanglement witnesses for 4N x 4N composite quantum systems or, equivalently, a new construction of nondecomposable positive maps in the algebra of 4N x 4N complex matrices. This construction provides natural generalization of the Robertson map. It is shown that their structural physical approximations give rise to entanglement breaking channels.



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