Gaussian quantum estimation of the loss parameter in a thermal environment
Journal article, 2022

Lossy bosonic channels play an important role in a number of quantum information tasks, since they well approximate thermal dissipation in an experiment. Here, we characterize their metrological power in the idler-free and entanglement-assisted cases, using respectively single- and two-mode Gaussian states as probes. In the problem of estimating the loss parameter, we study the power-constrained quantum Fisher information (QFI) for generic temperature and loss parameter regimes, showing qualitative behaviours of the optimal probes. We show semi-analytically that the two-mode squeezed-vacuum state optimizes the QFI for any value of the loss parameter and temperature. We discuss the optimization of the total QFI, where the number of probes is allowed to vary by keeping the total power constrained. In this context, we elucidate the role of the 'shadow-effect', or passive signature, for reaching a quantum advantage. Finally, we discuss the implications of our results for the quantum illumination and quantum reading protocols.

quantum sensing

Bosonic amplitude-damping channel

quantum reading

quantum Fisher information

quantum illumination

quantum metrology

Author

Robert Jonsson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Saab

Roberto Di Candia

Aalto University

Journal of Physics A: Mathematical and Theoretical

1751-8113 (ISSN) 1751-8121 (eISSN)

Vol. 55 38 385301

Subject Categories

Other Mathematics

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1088/1751-8121/ac83fa

More information

Latest update

10/27/2023