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arXiv · 0909.0256

Adaptive versus non-adaptive strategies for quantum channel discrimination

Aram W. Harrow·Avinatan Hassidim·Debbie W. Leung·John Watrous
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Abstract

We provide a simple example that illustrates the advantage of adaptive over non-adaptive strategies for quantum channel discrimination. In particular, we give a pair of entanglement-breaking channels that can be perfectly discriminated by means of an adaptive strategy that requires just two channel evaluations, but for which no non-adaptive strategy can give a perfect discrimination using any finite number of channel evaluations.

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Aram W. Harrow, Avinatan Hassidim, Debbie W. Leung, John Watrous. 2009-09-01. Adaptive versus non-adaptive strategies for quantum channel discrimination. https://doi.org/10.1103/physreva.81.032339

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