A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Quantum frequency estimation with conditional states of continuously monitored independent dephasing channels
Tekijät: Francesco Albarelli, Matteo A. C. Rossi, Marco G. Genoni
Kustantaja: World Scientific Publishing Co. Pte. Ltd.
Julkaisuvuosi: 2020
Journal: International Journal of Quantum Information
Artikkelin numero: 1941013
Vuosikerta: 18
Numero: 1
eISSN: 1793-6918
DOI: https://doi.org/10.1142/S0219749919410132
Verkko-osoite: https://www.worldscientific.com/doi/abs/10.1142/S0219749919410132
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/45415139
We discuss the problem of estimating a frequency via N-qubit probes undergoing independent dephasing channels that can be continuously monitored via homodyne or photo-detection. We derive the corresponding analytical solutions for the conditional states, for generic initial states and for arbitrary efficiency of the continuous monitoring. For the detection strategies considered, we show that: (i) in the case of perfect continuous detection, the quantum Fisher information (QFI) of the conditional states is equal to the one obtained in the noiseless dynamics; (ii) for smaller detection efficiencies, the QFI of the conditional state is equal to the QFI of a state undergoing the (unconditional) dephasing dynamics, but with an effectively reduced noise parameter.
Ladattava julkaisu This is an electronic reprint of the original article. |