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arXiv · 1812.07265

Robust self-testing of quantum systems via noncontextuality inequalities

Kishor Bharti·Maharshi Ray·Antonios Varvitsiotis·Naqueeb Ahmad Warsi·Adán Cabello·Leong-Chuan Kwek
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Abstract

Characterising unknown quantum states and measurements is a fundamental problem in quantum information processing. In this Letter, we provide a novel scheme to self-test local quantum systems using non-contextuality inequalities. Our work leverages the graph-theoretic framework for contextuality introduced by Cabello, Severini, and Winter, combined with tools from mathematical optimisation that guarantee the unicity of optimal solutions. As an application, we show that the celebrated Klyachko-Can-Biniciogglu-Shumovsky inequality and its generalisation to contextuality scenarios with odd n-cycle compatibility relations admit robust self-testing.

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Kishor Bharti, Maharshi Ray, Antonios Varvitsiotis, Naqueeb Ahmad Warsi, Adán Cabello, Leong-Chuan Kwek. 2018-12-18. Robust self-testing of quantum systems via noncontextuality inequalities. https://doi.org/10.1103/physrevlett.122.250403

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