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arXiv · 2507.10272

Efficient Measurement of Bosonic Non-Gaussianity

Kaifeng Bu·Bikun Li
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Abstract

Non-Gaussian states are essential resources in quantum information processing. In this work, we investigate methods for quantifying bosonic non-Gaussianity in many-body systems. Building on recent theoretical insights into the self-convolution properties of bosonic pure states, we introduce non-Gaussian entropy as a new measure to characterize non-Gaussianity in bosonic pure states. We further propose a practical protocol for measuring non-Gaussian entropy using three beam splitters and four copies of the input state. In addition, we extend this framework to mixed states, providing a general approach to quantifying non-Gaussianity. Our results offer a convenient and efficient method for characterizing bosonic non-Gaussianity, paving the way for its implementation on near-term experimental platforms.

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Kaifeng Bu, Bikun Li. 2025-07-14. Efficient Measurement of Bosonic Non-Gaussianity. https://arxiv.org/abs/2507.10272

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