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arXiv · 0707.1722

Multiplicativity of the maximal output 2-norm for depolarized Werner-Holevo channels

Spyridon Michalakis
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Abstract

We study the multiplicativity of the output 2-norm for depolarized Werner-Holevo channels and show that multiplicativity holds for a product of two identical channels in this class. Moreover, it shown that the depolarized Werner-Holevo channels do not satisfy the entrywise positivity condition introduced by C. King and M.B. Ruskai, which suggests that the main result is non-trivial.

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Spyridon Michalakis. 2007-07-11. Multiplicativity of the maximal output 2-norm for depolarized Werner-Holevo channels. https://doi.org/10.1063/1.2818737

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