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arXiv · 1907.05440

Quantum discord-breaking and discord-annihilating channels

Thao P. Le
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Abstract

Quantum discord-breaking channels were previously defined as the local channels that act on subsystem $A$ to produce classical-quantum states across system $AB$. However, unlike entanglement, discord is asymmetric. Here, we characterise the discord-breaking channels that act on subsystem $B$, thus completing the overall description of discord-breaking channels. We then introduce the notion of discord-annihilating channels, which act globally on system $AB$ to destroy quantum discord, and find their closed form. Discord-annihilating channels have clear operational description, involving subspace projections on subsystem $A$ and conditional preparation of fixed states on subsystem $B$.

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Thao P. Le. 2019-07-11. Quantum discord-breaking and discord-annihilating channels. https://arxiv.org/abs/1907.05440

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