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arXiv · 1706.07370

Sustained state-independent quantum contextual correlations from a single ion

F. M. Leupold·M. Malinowski·C. Zhang·V. Negnevitsky·J. Alonso·A. Cabello·J. P. Home
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Abstract

We use a single trapped-ion qutrit to demonstrate the violation of an input-state-independent non-contextuality inequality using a sequence of randomly chosen quantum non-demolition projective measurements. We concatenate 54 million sequential measurements of 13 observables, and violate an optimal non-contextual bound by 214 standard deviations. We use the same dataset to characterize imperfections including signaling and repeatability of the measurements. The experimental sequence was generated in real time with a quantum random number generator integrated into our control system to select the subsequent observable with a latency below 50 {\mu}s, which can be used to constrain hidden-variable models that might describe our results. The state-recycling experimental procedure is resilient to noise, self-correcting and independent of the qutrit state, substantiating the fact that quantumness is connected to measurements as opposed to designated states.

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F. M. Leupold, M. Malinowski, C. Zhang, V. Negnevitsky, J. Alonso, A. Cabello, J. P. Home. 2017-06-22. Sustained state-independent quantum contextual correlations from a single ion. https://doi.org/10.1103/physrevlett.120.180401

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