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arXiv · 0901.2118

All entangled states are useful for channel discrimination

M. Piani·J. Watrous
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Abstract

We prove that every entangled state is useful as a resource for the problem of minimum-error channel discrimination. More specifically, given a single copy of an arbitrary bipartite entangled state, it holds that there is an instance of a quantum channel discrimination task for which this state allows for a correct discrimination with strictly higher probability than every separable state.

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M. Piani, J. Watrous. 2009-07-16. All entangled states are useful for channel discrimination. https://doi.org/10.1103/physrevlett.102.250501

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