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arXiv · 2001.02668

Coherent Quantum Channel Discrimination

Mark M. Wilde
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Abstract

This paper introduces coherent quantum channel discrimination as a coherent version of conventional quantum channel discrimination. Coherent channel discrimination is phrased here as a quantum interactive proof system between a verifier and a prover, wherein the goal of the prover is to distinguish two channels called in superposition in order to distill a Bell state at the end. The key measure considered here is the success probability of distilling a Bell state, and I prove that this success probability does not increase under the action of a quantum superchannel, thus establishing this measure as a fundamental measure of channel distinguishability. Also, I establish some bounds on this success probability in terms of the success probability of conventional channel discrimination. Finally, I provide an explicit semi-definite program that can compute the success probability.

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Mark M. Wilde. 2020-01-08. Coherent Quantum Channel Discrimination. https://doi.org/10.1109/isit44484.2020.9174425

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