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arXiv · 1706.01924

Koashi-Winter relation for α-Renyi entropies

Tiago Debarba
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Abstract

This work presents a generalization of the Koashi-Winter relation for $α$-Renyi entropies. This result is based on the Renyi\apos s entropy version of quantum Jensen Shannon divergence. By means of this definition, a classical correlations quantifier $C_α(ρ_{AB}) = \sup_{ξ_{AB}^{M_B}} Q_α(ξ_{AB}^{M_B})$ is proposed, where the optimization is taken over the ensembles $ξ_{AB}^{M_B}$ created by the outputs of the local measurement process. The main result is applied to the capacity of a quantum classical channel over a tripartite pure state $ψ_{ABE}$, that is rated above in function of the probability of success to discriminate the states in the ensemble $ξ_{AE}^{M_E}$, created by the local dephasing over partition $E$, and the asymptotic log generalized robustness of partition $AB$. Some analytical results are calculated for classical correlations and entanglement of formation.

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Tiago Debarba. 2017-06-06. Koashi-Winter relation for α-Renyi entropies. https://arxiv.org/abs/1706.01924

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