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arXiv · 2211.04747

Optimizing quantum-enhanced Bayesian multiparameter estimation of phase and noise in practical sensors

Federico Belliardo·Valeria Cimini·Emanuele Polino·Francesco Hoch·Bruno Piccirillo·Nicolò Spagnolo·Vittorio Giovannetti·Fabio Sciarrino
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Abstract

Achieving quantum-enhanced performances when measuring unknown quantities requires developing suitable methodologies for practical scenarios, that include noise and the availability of a limited amount of resources. Here, we report on the optimization of sub-standard quantum limit Bayesian multiparameter estimation in a scenario where a subset of the parameters describes unavoidable noise processes in an experimental photonic sensor. We explore how the optimization of the estimation changes depending on which parameters are either of interest or are treated as nuisance ones. Our results show that optimizing the multiparameter approach in noisy apparata represents a significant tool to fully exploit the potential of practical sensors operating beyond the standard quantum limit for broad resources range.

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Federico Belliardo, Valeria Cimini, Emanuele Polino, Francesco Hoch, Bruno Piccirillo, Nicolò Spagnolo, Vittorio Giovannetti, Fabio Sciarrino. 2022-11-09. Optimizing quantum-enhanced Bayesian multiparameter estimation of phase and noise in practical sensors. https://doi.org/10.1103/physrevresearch.6.023201

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