Contextual Advantages and Certification for Maximum-Confidence Discrimination

Kieran Flatt, Hanwool Lee, Carles Roch I. Carceller, Jonatan Bohr Brask, Joonwoo Bae*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

30 Downloads (Pure)


One of the most fundamental results in quantum information theory is that no measurement can perfectly discriminate between nonorthogonal quantum states. In this work, we investigate quantum advantages for discrimination tasks over noncontextual theories by considering a maximum-confidence measurement that unifies different strategies of quantum state discrimination, including minimum-error and unambiguous discrimination. We first show that maximum-confidence discrimination, as well as unambiguous discrimination, contains contextual advantages. We then consider a semi-device-independent scenario of certifying maximum-confidence measurement. The scenario naturally contains undetected events, making it a natural setting to explore maximum-confidence measurements. We show that the certified maximum confidence in quantum theory also contains contextual advantages. Our results establish how the advantages of quantum theory over a classical model may appear in a realistic scenario of a discrimination task.

Original languageEnglish
Article number030337
JournalPRX Quantum
Issue number3
Number of pages19
Publication statusPublished - 2022


Dive into the research topics of 'Contextual Advantages and Certification for Maximum-Confidence Discrimination'. Together they form a unique fingerprint.

Cite this