Log-convex set of Lindblad semigroups acting on N-level system

  title={Log-convex set of Lindblad semigroups acting on N-level system},
  author={Fereshte Shahbeigi and David Amaro-Alcal{\'a} and Zbigniew Puchała and Karol Życzkowski},
  journal={Journal of Mathematical Physics},
We analyze the set ${\cal A}_N^Q$ of mixed unitary channels represented in the Weyl basis and accessible by a Lindblad semigroup acting on an $N$-level quantum system. General necessary and sufficient conditions for a mixed Weyl quantum channel of an arbitrary dimension to be accessible by a semigroup are established. The set ${\cal A}_N^Q$ is shown to be log--convex and star-shaped with respect to the completely depolarizing channel. A decoherence supermap acting in the space of Lindblad… 

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