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Teleportation as a Depolarizing Quantum Channel, Relative Entropy and Classical Capacity

G. Bowen·S. Bose
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Abstract

We show that standard teleportation with an arbitrary mixed state resource is equivalent to a generalized depolarizing channel with probabilities given by the maximally entangled components of the resource. This enables the usage of any quantum channel as a generalized depolarizing channel without additional twirling operations. It also provides a nontrivial upper bound on the entanglement of a class of mixed states. Our result allows a consistent and statistically motivated quantification of teleportation success in terms of the relative entropy and this quantification can be related to a classical capacity.

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G. Bowen, S. Bose. 2001-12-05. Teleportation as a Depolarizing Quantum Channel, Relative Entropy and Classical Capacity. https://doi.org/10.1103/physrevlett.87.267901

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