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arXiv · 2307.08258

Mixed-state additivity properties of magic monotones based on quantum relative entropies for single-qubit states and beyond

Roberto Rubboli·Ryuji Takagi·Marco Tomamichel
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Abstract

We prove that the stabilizer fidelity is multiplicative for the tensor product of an arbitrary number of single-qubit states. We also show that the relative entropy of magic becomes additive if all the single-qubit states but one belong to a symmetry axis of the stabilizer octahedron. We extend the latter results to include all the $\alpha$-$z$ R\'enyi relative entropy of magic. This allows us to identify a continuous set of magic monotones that are additive for single-qubit states. We also show that all the monotones mentioned above are additive for several standard two and three-qubit states subject to depolarizing noise. Finally, we obtain closed-form expressions for several states and tighter lower bounds for the overhead of probabilistic one-shot magic state distillation.

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Roberto Rubboli, Ryuji Takagi, Marco Tomamichel. 2023-07-17. Mixed-state additivity properties of magic monotones based on quantum relative entropies for single-qubit states and beyond. https://doi.org/10.22331/q-2024-10-04-1492

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