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arXiv · 0902.2834

The classical capacity of quantum channels with memory

Tony Dorlas·Ciara Morgan
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Abstract

We investigate the classical capacity of two quantum channels with memory: a periodic channel with depolarizing channel branches, and a convex combination of depolarizing channels. We prove that the capacity is additive in both cases. As a result, the channel capacity is achieved without the use of entangled input states. In the case of a convex combination of depolarizing channels the proof provided can be extended to other quantum channels whose classical capacity has been proved to be additive in the memoryless case.

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Tony Dorlas, Ciara Morgan. 2009-02-17. The classical capacity of quantum channels with memory. https://doi.org/10.1103/physreva.79.032320

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