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arXiv · 2301.07428

New constructive counterexamples to additivity of minimum output R\'enyi p-entropy of quantum channels

Krzysztof Szczygielski·Michał Studziński
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Abstract

In this paper, we present new families of quantum channels for which corresponding minimum output R\'enyi $p$-entropy is not additive. Our manuscript is motivated by the results of Grudka et al., J. Phys. A: Math. Theor. 43 425304 and we focus on channels characterized by both extensions and subspaces of the antisymmetric subspace in $\mathbb{C}^d \otimes \mathbb{C}^d$, which exhibit additivity breaking for $p>2$.

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Krzysztof Szczygielski, Michał Studziński. 2023-01-18. New constructive counterexamples to additivity of minimum output R\'enyi p-entropy of quantum channels. https://doi.org/10.1109/tit.2024.3446191

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