Bounding the forward classical capacity of bipartite quantum channels

Dawei Ding; Sumeet Khatri; Yihui Quek; Peter W. Shor; Xin Wang; Mark M. Wilde

doi:10.1109/tit.2022.3233924

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arXiv · 2010.01058

Bounding the forward classical capacity of bipartite quantum channels

Dawei Ding·Sumeet Khatri·Yihui Quek·Peter W. Shor·Xin Wang·Mark M. Wilde

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Abstract

We introduce various measures of forward classical communication for bipartite quantum channels. Since a point-to-point channel is a special case of a bipartite channel, the measures reduce to measures of classical communication for point-to-point channels. As it turns out, these reduced measures have been reported in prior work of Wang et al. on bounding the classical capacity of a quantum channel. As applications, we show that the measures are upper bounds on the forward classical capacity of a bipartite channel. The reduced measures are upper bounds on the classical capacity of a point-to-point quantum channel assisted by a classical feedback channel. Some of the various measures can be computed by semi-definite programming.

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Dawei Ding, Sumeet Khatri, Yihui Quek, Peter W. Shor, Xin Wang, Mark M. Wilde. 2020-10-02. Bounding the forward classical capacity of bipartite quantum channels. https://doi.org/10.1109/tit.2022.3233924

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