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arXiv · 1903.08420

Generalizations of $2$-dimensional diagonal quantum channels with constant Frobenius norm

Ivan Sergeev
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Abstract

We introduce the set of quantum channels with constant Frobenius norm, the set of diagonal channels and the notion of equivalence of one-parameter families of channels. First, we show that all diagonal $2$-dimensional channels with constant Frobenius norm are equivalent. Next, we generalize four one-parameter families of $2$-dimensional diagonal channels with constant Frobenius norm to an arbitrary dimension $n$. Finally, we prove that the generalizations are not equivalent in any dimension $n \ge 3$.

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Ivan Sergeev. 2019-03-20. Generalizations of $2$-dimensional diagonal quantum channels with constant Frobenius norm. https://doi.org/10.1016/s0034-4877(19)30055-2

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