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arXiv · 1810.09642

Amending coherence-breaking channels via unitary operations

Long-Mei Yang·Bin Chen·Tao Li·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

The coherence-breaking channels play a significant role in quantum information theory. We study the coherence-breaking channels and give a method to amend the coherence-breaking channels by applying unitary operations. For given incoherent channel $\Phi$, we give necessary and sufficient conditions for the channel to be a coherence-breaking channel and amend it via unitary operations. For qubit incoherent channels $\Phi$ that are not coherence-breaking ones, we consider the mapping $\Phi\circ\Phi$ and present the conditions for coherence-breaking and channel amendment as well.

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Long-Mei Yang, Bin Chen, Tao Li, Shao-Ming Fei, Zhi-Xi Wang. 2018-10-23. Amending coherence-breaking channels via unitary operations. https://doi.org/10.1007/s10773-018-3890-4

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