Noise-robust preparation contextuality shared between any number of observers via unsharp measurements

• Main Authors: Hammad Anwer, Natalie Wilson, Ralph Silva, Sadiq Muhammad, Armin Tavakoli, Mohamed Bourennane
• Format: Article
• Language: English
• Published: Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften 2021-09-01
• Series: Quantum
• Online Access: https://quantum-journal.org/papers/q-2021-09-28-551/pdf/

Multiple observers who independently harvest nonclassical correlations from a single physical system share the system's ability to enable quantum correlations. We show that any number of independent observers can share the preparation contextual outcome statistics enabled by state ensembles in quantum theory. Furthermore, we show that even in the presence of any amount of white noise, there exists quantum ensembles that enable such shared preparation contextuality. The findings are experimentally realised by applying sequential unsharp measurements to an optical qubit ensemble which reveals three shared demonstrations of preparation contextuality.