Limitations of Gaussian measurements in quantum imaging

Yunkai Wang; Sisi Zhou

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arXiv · 2503.06363

Limitations of Gaussian measurements in quantum imaging

Yunkai Wang·Sisi Zhou

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Abstract

Imaging thermal sources naturally yields Gaussian states at the receiver, raising the question of whether Gaussian measurements can perform optimally in quantum imaging. In this work, we establish no-go theorems on the performance of Gaussian measurements for imaging thermal sources in the limit of mean photon number per temporal mode $\epsilon \to 0$ or source size $L \to 0$. We show that non-Gaussian measurements can outperform any Gaussian measurement in the scaling of the estimation variance with $\epsilon$ (or $L$). We also present several examples to illustrate the no-go results.

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Yunkai Wang, Sisi Zhou. 2025-03-09. Limitations of Gaussian measurements in quantum imaging. https://arxiv.org/abs/2503.06363

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