Problems of Information Transmission

, Volume 49, Issue 3, pp 224–231 | Cite as

On estimating the output entropy of the tensor product of a phase-damping channel and an arbitrary channel

Information Theory


We obtain a lower estimate for the output entropy of a tensor product of the quantum phase-damping channel and an arbitrary channel. We show that this estimate immediately implies that strong superadditivity of the output entropy holds for this channel as well as for the quantum depolarizing channel.


Tensor Product Information Transmission Quantum Channel Output Entropy Quantum Relative Entropy 


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© Pleiades Publishing, Inc. 2013

Authors and Affiliations

  1. 1.Steklov Mathematical InstituteRussian Academy of SciencesMoscowRussia

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