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arXiv · 2503.17235

Infinite-fold Asymptotic Quantum Advantage in Classical Correlation Sensing

Janis Nötzel·Pere Munar-Vallespir
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Abstract

We study the hypothesis testing problem of distinguishing between correlated thermal noise and uncorrelated thermal noise of the same average energy on $K$ detectors in asymptotic asymmetric hypothesis testing. We compare the performance of heterodyne or homodyne detection with classical post-processing, the most general quantum strategy (involving any arbitrary measurement), and a simple strategy involving a photonic chip and On-Off detection. When the average received energy per detector goes to zero, the photonic chip strategy asymptotically achieves the optimal decrease in the error, while heterodyne/homodyne measurements do not. Thus, we show that linear optics and On-Off measurement are enough to achieve better detection than classical methods when detecting correlations in thermal optical signals.

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Janis Nötzel, Pere Munar-Vallespir. 2025-03-21. Infinite-fold Asymptotic Quantum Advantage in Classical Correlation Sensing. https://arxiv.org/abs/2503.17235

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