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arXiv · 2212.14343

Continuous-Variable Nonclassicality Detection under Coarse-Grained Measurement

Chan Roh·Young-Do Yoon·Jiyong Park·Young-Sik Ra
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Abstract

Coarse graining is a common imperfection of realistic quantum measurement, obstructing the direct observation of quantum features. Under highly coarse-grained measurement, we experimentally detect the continuous-variable nonclassicality of both Gaussian and non-Gaussian states. Remarkably, we find that this coarse-grained measurement outperforms the conventional fine-grained measurement for nonclassicality detection: it detects nonclassicality beyond the reach of the variance criterion, and furthermore, it exhibits stronger statistical significance than the high-order moments method. Our work shows the usefulness of coarse-grained measurement by providing a reliable and efficient way of nonclassicality detection for quantum technologies.

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Chan Roh, Young-Do Yoon, Jiyong Park, Young-Sik Ra. 2022-12-29. Continuous-Variable Nonclassicality Detection under Coarse-Grained Measurement. https://doi.org/10.1103/physrevresearch.5.043057

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