Kramers-Kronig relations and precision limits in quantum phase estimation
Quantum Physics
2022-04-21 v1
Abstract
The ultimate precision in any measurement is dictated by the physical process implementing the observation. The methods of quantum metrology have now succeeded in establishing bounds on the achievable precision for phase measurements over noisy channels. In particular, they demonstrate how the Heisenberg scaling of the precision can not be attained in these conditions. Here we discuss how the ultimate bound in presence of loss has a physical motivation in the Kramers-Kronig relations and we show how they link the precision on the phase estimation to that on the loss parameter.
Cite
@article{arxiv.2107.10521,
title = {Kramers-Kronig relations and precision limits in quantum phase estimation},
author = {Ilaria Gianani and Marco Barbieri and Francesco Albarelli and Adriano Verna and Valeria Cimini and Rafal Demkowicz-Dobrzanski},
journal= {arXiv preprint arXiv:2107.10521},
year = {2022}
}