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arXiv · 2111.09264

Noninvertibility as a requirement for creating a semigroup under convex combinations of channels

Vinayak Jagadish·R. Srikanth·Francesco Petruccione
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Abstract

We study the conditions under which a semigroup is obtained upon convex combinations of channels. In particular, we study the set of Pauli and generalized Pauli channels. We find that mixing only semigroups can never produce a semigroup. Counter-intuitively, we find that for a convex combination to yield a semigroup, most of the input channels have to be noninvertible.

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Vinayak Jagadish, R. Srikanth, Francesco Petruccione. 2021-11-17. Noninvertibility as a requirement for creating a semigroup under convex combinations of channels. https://doi.org/10.1103/physreva.105.032422

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