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arXiv · 2102.08722

Quantifying necessary quantum resources for nonlocality

Lucas Tendick·Hermann Kampermann·Dagmar Bruß
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Abstract

Nonlocality is one of the most important resources for quantum information protocols. The observation of nonlocal correlations in a Bell experiment is the result of appropriately chosen measurements and quantum states. We quantify the minimal purity to achieve a certain Bell value for any Bell operator. Since purity is the most fundamental resource of a quantum state, this enables us also to quantify the necessary coherence, discord, and entanglement for a given violation of two-qubit correlation inequalities. Our results shine new light on the CHSH inequality by showing that for a fixed Bell violation an increase in the measurement resources does not always lead to a decrease of the minimal state resources.

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Lucas Tendick, Hermann Kampermann, Dagmar Bruß. 2021-02-17. Quantifying necessary quantum resources for nonlocality. https://doi.org/10.1103/physrevresearch.4.l012002

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