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arXiv · 1601.06727

Optimal Bounds on Functions of Quantum States under Quantum Channels

Chi-Kwong Li·Diane Christine Pelejo·Kuo-Zhong Wang
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Abstract

Let $ρ_1, ρ_2$ be quantum states and $(ρ_1,ρ_2) \mapsto D(ρ_1, ρ_2)$ be a scalar function such as the trace norm, the fidelity, and the relative entropy, etc. We determine optimal bounds for $D(ρ_1, Φ(ρ_2))$ for $Φ\in \mathcal{S}$ for different class of functions $D(\cdot, \cdot)$, where $\mathcal{S}$ is the set of unitary quantum channels, the set of mixed unitary channels, the set of unital quantum channels, and the set of all quantum channels.

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Chi-Kwong Li, Diane Christine Pelejo, Kuo-Zhong Wang. 2016-04-11. Optimal Bounds on Functions of Quantum States under Quantum Channels. https://arxiv.org/abs/1601.06727

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