Nonconvexity of private capacity and classical environment-assisted capacity of a quantum channel
Accepted version
Peer-reviewed
Repository URI
Repository DOI
Change log
Authors
Elkouss, D
Strelchuk, Sergii https://orcid.org/0000-0001-8390-3034
Abstract
The capacity of classical channels is convex. This is not the case for the quantum capacity of a channel: The capacity of a mixture of different quantum channels exceeds the mixture of the individual capacities and thus is nonconvex. Here we show that this effect goes beyond the quantum capacity and holds for the private and classical environment-assisted capacities of quantum channels.
Description
Keywords
5108 Quantum Physics, 51 Physical Sciences
Journal Title
Physical Review A
Conference Name
Journal ISSN
2469-9926
2469-9934
2469-9934
Volume Title
94
Publisher
American Physical Society
Publisher DOI
Sponsorship
European Commission (600700)
S.S. acknowledges the support of Sidney Sussex College and European Union under project QALGO (Grant Agreement No. 600700). D.E. has been partially supported by STW, the NWO Vidi grant “Large quantum networks from small quantum devices,” and by the project HyQuNet (Grant No. TEC2012-35673), funded by Ministerio de Econom´ıa y Competitividad (MINECO), Spain.