Strong Converse Rates for Quantum Communication

Institute of Electrical and Electronics Engineers
Publication Type:
Journal Article
IEEE Transactions on Information Theory, 2017, 63 (1), pp. 715 - 727
Issue Date:
Full metadata record
Files in This Item:
Filename Description Size
1406.2946v4.pdfAccepted Manuscript version271.9 kB
Adobe PDF
© 2016 IEEE. We revisit a fundamental open problem in quantum information theory, namely whether it is possible to transmit quantum information at a rate exceeding the channel capacity if we allow for a non-vanishing probability of decoding error. Here we establish that the Rains information of any quantum channel is a strong converse rate for quantum communication: For any sequence of codes with rate exceeding the Rains information of the channel, we show that the fidelity vanishes exponentially fast as the number of channel uses increases. This remains true even if we consider codes that perform classical post-processing on the transmitted quantum data. As an application of this result, for generalized dephasing channels we show that the Rains information is also achievable, and thereby establish the strong converse property for quantum communication over such channels. Thus we conclusively settle the strong converse question for a class of quantum channels that have a non-trivial quantum capacity.
Please use this identifier to cite or link to this item: