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arXiv · 2110.02908

Non-asymptotic Heisenberg scaling: experimental metrology for a wide resources range

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

Adopting quantum resources for parameter estimation discloses the possibility to realize quantum sensors operating at a sensitivity beyond the standard quantum limit. Such approach promises to reach the fundamental Heisenberg scaling as a function of the employed resources $N$ in the estimation process. Although previous experiments demonstrated precision scaling approaching Heisenberg-limited performances, reaching such regime for a wide range of $N$ remains hard to accomplish. Here, we show a method which suitably allocates the available resources reaching Heisenberg scaling without any prior information on the parameter. We demonstrate experimentally such an advantage in measuring a rotation angle. We quantitatively verify Heisenberg scaling for a considerable range of $N$ by using single-photon states with high-order orbital angular momentum, achieving an error reduction greater than $10$ dB below the standard quantum limit. Such results can be applied to different scenarios, opening the way to the optimization of resources in quantum sensing.

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Valeria Cimini, Emanuele Polino, Federico Belliardo, Francesco Hoch, Bruno Piccirillo, Nicolò Spagnolo, Vittorio Giovannetti, Fabio Sciarrino. 2021-10-06. Non-asymptotic Heisenberg scaling: experimental metrology for a wide resources range. https://doi.org/10.1038/s41534-023-00691-y

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