https://doi.org/10.1140/epjp/s13360-021-02337-4
Regular Article
Non-adaptive Heisenberg-limited metrology with multi-channel homodyne measurements
1
School of Mathematics and Physics, University of Portsmouth, PO1 3QL, Portsmouth, UK
2
Dipartimento di Fisica and MECENAS, Università di Bari, 70126, Bari, Italy
3
INFN, Sezione di Bari, 70126, Bari, Italy
4
Institute of Cosmology and Gravitation, University of Portsmouth, PO1 3FX, Portsmouth, UK
Received:
7
October
2021
Accepted:
29
December
2021
Published online:
17
January
2022
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.
© The Author(s) 2022
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