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arXiv · 2409.04425

Qubit magic-breaking channels

Ayan Patra·Rivu Gupta·Alessandro Ferraro·Aditi Sen De
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Abstract

We develop a notion of quantum channels that can make states useless for universal quantum computation by destroying their magic (non-stabilizerness) - we refer to them as magic-breaking channels. We establish the properties of these channels in arbitrary dimensions. We prove the necessary and sufficient criteria for qubit channels to be magic-breaking and present an algorithm for determining the same. Moreover, we provide compact criteria in terms of the parameters for several classes of qubit channels to be magic-breaking under various post-processing operations. Further, we investigate the necessary and sufficient conditions for the tensor product of multiple qubit channels to be magic-breaking. We establish implications of the same for the dynamical resource theory of magic preservability.

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Ayan Patra, Rivu Gupta, Alessandro Ferraro, Aditi Sen De. 2024-09-06. Qubit magic-breaking channels. https://arxiv.org/abs/2409.04425

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