Related papers: Phase-covariant mixtures of non-unital qubit maps

Phase-covariant mixtures of non-unital qubit maps

URL: http://arxiv.org/abs/2206.10742v1
Date: Tue, 21 Jun 2022 21:35:17 GMT
Title: Phase-covariant mixtures of non-unital qubit maps
Authors: Katarzyna Siudzi\'nska
Abstract summary: We analyze convex combinations of non-unital qubit maps that are phase-covariant. We show that mixing non-unital channels can result in restoring the unitality, whereas mixing commutative maps can lead to non-commutativity.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: We analyze convex combinations of non-unital qubit maps that are phase-covariant. In particular, we consider the behavior of maps that combine amplitude damping, inverse amplitude damping, and pure dephasing. We show that mixing non-unital channels can result in restoring the unitality, whereas mixing commutative maps can lead to non-commutativity. For the convex combinations of Markovian semigroups, we prove that classical uncertainties cannot break quantum Markovianity. Moreover, contrary to the Pauli channel case, the semigroup can be recovered only by mixing two other semigroups.

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