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arXiv · 2208.14473

Experimental multiparameter quantum metrology in adaptive regime

Mauro Valeri·Valeria Cimini·Simone Piacentini·Francesco Ceccarelli·Emanuele Polino·Francesco Hoch·Gabriele Bizzarri·Giacomo Corrielli·Nicolò Spagnolo·Roberto Osellame·Fabio Sciarrino
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Abstract

Relevant metrological scenarios involve the simultaneous estimation of multiple parameters. The fundamental ingredient to achieve quantum-enhanced performances is based on the use of appropriately tailored quantum probes. However, reaching the ultimate resolution allowed by physical laws requires non trivial estimation strategies both from a theoretical and a practical point of view. A crucial tool for this purpose is the application of adaptive learning techniques. Indeed, adaptive strategies provide a flexible approach to obtain optimal parameter-independent performances, and optimize convergence to the fundamental bounds with limited amount of resources. Here, we combine on the same platform quantum-enhanced multiparameter estimation attaining the corresponding quantum limit and adaptive techniques. We demonstrate the simultaneous estimation of three optical phases in a programmable integrated photonic circuit, in the limited resource regime. The obtained results show the possibility of successfully combining different fundamental methodologies towards transition to quantum sensors applications.

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Mauro Valeri, Valeria Cimini, Simone Piacentini, Francesco Ceccarelli, Emanuele Polino, Francesco Hoch, Gabriele Bizzarri, Giacomo Corrielli, Nicolò Spagnolo, Roberto Osellame, Fabio Sciarrino. 2022-08-30. Experimental multiparameter quantum metrology in adaptive regime. https://doi.org/10.1103/physrevresearch.5.013138

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