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arXiv · 1503.09176

Conditions for coherence transformations under incoherent operations

Shuanping Du·Zhaofang Bai·Yu Guo
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Abstract

We build the counterpart of the celebrated Nielsen's theorem for coherence manipulation in this paper. This offers an affirmative answer to the open question: whether, given two states $ρ$ and $σ$, either $ρ$ can be transformed into $σ$ or vice versa under incoherent operations [Phys. Rev. Lett. \textbf{113}, 140401(2014)]. As a consequence, we find that there exist essentially different types of coherence. Moreover, incoherent operations can be enhanced in the presence of certain coherent states. These extra states are coherent catalysts: they allow uncertain incoherent operations to be realized, without being consumed in any way. Our main result also sheds a new light on the construction of coherence measures.

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Shuanping Du, Zhaofang Bai, Yu Guo. 2016-05-20. Conditions for coherence transformations under incoherent operations. https://doi.org/10.1103/physreva.91.052120

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