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arXiv · 2601.16570

Certification of quantum properties with imperfect measurements

Leonardo Zambrano·Teodor Parella-Dilmé·Antonio Acín·Donato Farina
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Abstract

The accurate characterization of quantum systems is essential for the advancement of quantum technologies. In particular, certifying convex functions of quantum states plays a central role in many applications. We present a certification method for experimentally prepared quantum states that accounts for both shot noise and measurement imperfections in the data-acquisition stage. Building upon previous work, our method extends confidence regions to accommodate imperfect control over measurements. The values of the functions can then be bounded using convex optimization techniques. We provide explicit prescriptions for quantifying the noise contribution from finite statistics and for estimating the effect of measurement imperfections. By jointly incorporating statistical and systematic errors, the method yields a robust certification framework for quantum experiments.

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Leonardo Zambrano, Teodor Parella-Dilmé, Antonio Acín, Donato Farina. 2026-01-23. Certification of quantum properties with imperfect measurements. https://arxiv.org/abs/2601.16570

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