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arXiv · 1402.4120

Random-Unitary Depolarization Ensures the Correctability of All Quantum Channels

Samuel R. Hedemann
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Abstract

We prove that if any error channel has a Kraus decomposition that is simultaneously correctable and Hilbert-Schmidt (HS) complete, then the existence of Kraus sets with these properties guarantees the correctability of all quantum channels. As a proof of the existence of such Kraus sets, the $n$-level depolarization channel is shown to have a random-unitary (RU) decomposition that is both HS complete and correctable due its RU nature, thereby proving that all quantum channels are correctable. As an application, conditions for universal error-correction operations are presented.

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Samuel R. Hedemann. 2014-02-17. Random-Unitary Depolarization Ensures the Correctability of All Quantum Channels. https://arxiv.org/abs/1402.4120

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