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arXiv · 2501.06846

Eternal non-Markovianity of qubit maps

Vinayak Jagadish·R. Srikanth
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Abstract

As is well known, unital Pauli maps can be eternally non-CP-divisible. In contrast, here we show that in the case of non-unital maps, eternal non-Markovianity in the non-unital part is ruled out. In the unital case, the eternal non-Markovianity can be obtained by a convex combination of two dephasing semigroups, but not all three of them. We study these results and ramifications arising from them.

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Vinayak Jagadish, R. Srikanth. 2025-01-12. Eternal non-Markovianity of qubit maps. https://arxiv.org/abs/2501.06846

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