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arXiv · 2301.08670

Distributed quantum incompatibility

Lucas Tendick·Hermann Kampermann·Dagmar Bruß
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Abstract

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a measurement scheme. However, it is generally unclear how large this enhancement is and on what it depends. Here, we show that the incompatibility which is gained via additional measurements is upper and lower bounded by certain functions of the incompatibility of subsets of the available measurements. We prove the tightness of some of our bounds by providing explicit examples based on mutually unbiased bases. Finally, we discuss the consequences of our results for the nonlocality that can be gained by enlarging the number of measurements in a Bell experiment.

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Lucas Tendick, Hermann Kampermann, Dagmar Bruß. 2023-01-20. Distributed quantum incompatibility. https://doi.org/10.1103/physrevlett.131.120202

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