nt - p h / 99 12 03 3 v 1 7 D ec 1 99 9 Mixedness and teleportation
نویسندگان
چکیده
We show that on exceeding a certain degree of mixedness (as quantified by the von Neumann entropy), entangled states become useless for teleporatation. By increasing the dimension of the entangled systems, this entropy threshold can be made arbitrarily close to maximal. This entropy is found to exceed the entropy threshold sufficient to ensure the failure of dense coding.
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