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arXiv · 2404.02709

Certification of multi-qubit quantum systems with temporal inequalities

Gautam Sharma·Chellasamy Jebarathinam·Sk Sazim·Remigiusz Augusiak
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Abstract

Demonstrating contextual correlations in quantum theory through the violation of a non-contextuality inequality necessarily needs some ``contexts" and thus assumes some compatibility relations between the measurements. As a result, any self-testing protocol based on the maximal violation of such inequality is not free from such assumptions. In this work, we propose temporal inequalities derived from non-contextuality inequalities for multi-qubit systems without assuming any compatibility relations among the measurements. We demonstrate that the new inequalities can be maximally violated via a sequential measurement scenario. Moreover, using the maximal violation of these temporal inequalities we are able to certify multi-qubit graph states and the measurements.

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Gautam Sharma, Chellasamy Jebarathinam, Sk Sazim, Remigiusz Augusiak. 2024-04-03. Certification of multi-qubit quantum systems with temporal inequalities. https://doi.org/10.1088/1367-2630/ad86e5

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