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arXiv · 2110.03582

Non-adaptive Heisenberg-limited metrology with multi-channel homodyne measurements

Danilo Triggiani·Paolo Facchi·Vincenzo Tamma
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Abstract

We show a protocol achieving the ultimate Heisenberg-scaling sensitivity in the estimation of a parameter encoded in a generic linear network, without employing any auxiliary networks, and without the need of any prior information on the parameter nor on the network structure. As a result, this protocol does not require a prior coarse estimation of the parameter, nor an adaptation of the network. The scheme we analyse consists of a single-mode squeezed state and homodyne detectors in each of the $M$ output channels of the network encoding the parameter, making it feasible for experimental applications.

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Danilo Triggiani, Paolo Facchi, Vincenzo Tamma. 2021-10-07. Non-adaptive Heisenberg-limited metrology with multi-channel homodyne measurements. https://doi.org/10.1140/epjp/s13360-021-02337-4

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