Quantum state discrimination with applications in contextuality and randomness certification

Qin Fan, Zhao-Di Liu, Rui-Heng Miao +2 more

Frédéric Dupuis, Serge Fehr, Philippe Lamontagne +1 more

Ulrike Futschik

Carles Roch i Carceller, Kieran Flatt, Hanwool Lee +2 more

We compare the power of quantum and classical physics in terms of randomness certification from devices which are only partially characterized. We study randomness certification based on state discrimination and take noncontextuality as the notion of classicality. A contextual advantage was recently shown to exist for state discrimination. Here, we develop quantum and noncontextual semi-device independent protocols for random-number generation based on maximum-confidence discrimination, which generalizes unambiguous and minimum-error state discrimination. We show that, for quantum eavesdroppers, quantum devices can certify more randomness than noncontextual ones whenever none of the input states are unambiguously identified. That is, a quantum-over-classical advantage exists.

János A. Bergou

Carles Roch i Carceller, Kieran Flatt, Hanwool Lee +2 more

We compare the power of quantum and classical physics in terms of randomness certification from devices which are only partially characterized. We study randomness certification based on state discrimination and take noncontextuality as the notion of classicality. A contextual advantage was recently shown to exist for state discrimination. Here, we develop quantum and noncontextual semi-device independent protocols for random-number generation based on maximum-confidence discrimination, which generalizes unambiguous and minimum-error state discrimination. We show that, for quantum eavesdroppers, quantum devices can certify more randomness than noncontextual ones whenever none of the input states are unambiguously identified. That is, a quantum-over-classical advantage exists.