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arXiv · 1909.00926

Entanglement enhanced distinguishability of coherence-breaking channels

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

Originated from the superposition principle in quantum mechanics, coherence has been extensively studied as a kind important resource in quantum information processing. We investigate the distinguishability of coherence-breaking channels with the help of quantum entanglement. By explicitly computing the minimal error probability of channel discrimination, it is shown that entanglement can enhance the capacity of coherence-breaking channel distinguishability with same types for some cases while cannot enhanced for some other cases. For coherence-breaking channels with different types, the channel distinguishability cannot be enhanced via entanglement.

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Long-Mei Yang, Tao Li, Shao-Ming Fei, Zhi-Xi Wang. 2019-09-03. Entanglement enhanced distinguishability of coherence-breaking channels. https://doi.org/10.1142/s0219749919500369

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