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Operational advantage of quantum resources in subchannel discrimination

Takagi, Ryuji; Regula, Bartosz; Bu, Kaifeng; Liu, Zi-Wen; Adesso, Gerardo


Ryuji Takagi

Bartosz Regula

Kaifeng Bu

Zi-Wen Liu


One of the central problems in the study of quantum resource theories is to provide a given resource with an operational meaning, characterizing physical tasks in which the resource can give an explicit advantage over all resourceless states. We show that this can always be accomplished for all convex resource theories. We establish in particular that any resource state enables an advantage in a channel discrimination task, allowing for a strictly greater success probability than any state without the given resource. Furthermore, we find that the generalized robustness measure serves as an exact quantifier for the maximal advantage enabled by the given resource state in a class of subchannel discrimination problems, providing a universal operational interpretation to this fundamental resource quantifier. We also consider a wider range of subchannel discrimination tasks and show that the generalized robustness still serves as the operational advantage quantifier for several well-known theories such as entanglement, coherence, and magic.


Takagi, R., Regula, B., Bu, K., Liu, Z., & Adesso, G. (2019). Operational advantage of quantum resources in subchannel discrimination. Physical Review Letters, 122(14), Article 140402.

Journal Article Type Article
Acceptance Date Feb 2, 2019
Online Publication Date Apr 10, 2019
Publication Date Apr 12, 2019
Deposit Date Apr 29, 2019
Publicly Available Date Apr 29, 2019
Journal Physical Review Letters
Print ISSN 0031-9007
Electronic ISSN 1079-7114
Publisher American Physical Society
Peer Reviewed Peer Reviewed
Volume 122
Issue 14
Article Number 140402
Keywords General Physics and Astronomy
Public URL
Publisher URL
Additional Information Operational Advantage of Quantum Resources in Subchannel Discrimination, Ryuji Takagi, Bartosz Regula, Kaifeng Bu, Zi-Wen Liu, and Gerardo Adesso, Phys. Rev. Lett. 122, 140402.


Operational Advantage of Quantum Resources in Subchannel Discrimination (189 Kb)

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