ar X iv : q ua nt - p h / 05 06 09 5 v 1 1 3 Ju n 20 05 Schmidt states and positivity of linear maps
نویسنده
چکیده
Using pure entangled Schmidt states, we show that m-positivity of a map is bounded by the ranks of its negative Kraus matrices. We also give an algebraic condition for a map to be m-positive. We interpret these results in the context of positive maps as entanglement witnesses, and find that only 1-positive maps are needed for testing entanglement.
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تاریخ انتشار 2005