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arXiv · 2609.38678

Exponential separation in sensing continuous signals via squeezing

Francesco Anna Mele·Nadine Meister·Haimeng Zhao·Senrui Chen·Hsin-Yuan Huang
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Abstract

Quantum sensing traditionally focuses on using quantum resources such as squeezing and entanglement to improve precision for sensing fixed signals. However, in many applications such as gravitational-wave detection and electromagnetic-field sensing, the signal evolves continuously and varies through time. Additionally, the learner is free to prepare, control, and measure the sensor at arbitrary times, possibly chosen adaptively. In this work, we establish exponential separation in sensing time for continuously evolving signals due to the available squeezing. The signals we study are characterized by a pattern size $T$, and we find that a sensor with squeezing at least $ω(\sqrt{\log T})$ offers a $\mathrm{poly}(T)$ sensing time, whereas those with squeezing at most $o(\sqrt{\log T})$ must use an exponential sensing time in $T$.

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Francesco Anna Mele, Nadine Meister, Haimeng Zhao, Senrui Chen, Hsin-Yuan Huang. 2026-09-30. Exponential separation in sensing continuous signals via squeezing. https://arxiv.org/abs/2609.38678

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