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arXiv · 2505.08756

Designing open quantum systems for enabling quantum enhanced sensing through classical measurements

Robert Mattes·Albert Cabot·Federico Carollo·Igor Lesanovsky
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Abstract

Quantum systems in nonequilibrium conditions, where coherent many-body interactions compete with dissipative effects, can feature rich phase diagrams and emergent critical behavior. Associated collective effects, together with the continuous observation of quanta dissipated into the environment -- typically photons -- allow to achieve quantum enhanced parameter estimation. However, protocols for tapping this enhancement typically involve intricate measurements on the combined system-environment state. Here we show that many-body quantum enhancement can in fact be obtained through classical measurements, such as photon counting and homodyne detection. We illustrate this in detail for a class of open spin-boson models which can be realized in trapped-ion or cavity QED setups. Our findings highlight a route towards the design of systems that enable a practical implementation of quantum enhanced metrology through continuous classical measurements.

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Robert Mattes, Albert Cabot, Federico Carollo, Igor Lesanovsky. 2025-05-13. Designing open quantum systems for enabling quantum enhanced sensing through classical measurements. https://doi.org/10.1103/5gh9-nmv8

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