Extracting filtered signal statistics of continuously measured quantum systems
Loading...
Date
2026-03-25
Authors
Kiely, Anthony
Landi, Gabriel
Journal Title
Journal ISSN
Volume Title
Publisher
American Physical Society
Published Version
Abstract
The joint state of a continuously monitored quantum system and the classical filtered measurement record has recently been shown to be described by a quantum Fokker-Planck master equation [Phys. Rev. Lett. 129, 050401 (2022)]. We present a deterministic approach to compute the steady state of the system and detector. The method is shown to become particularly efficient in the absence of feedback, which we exploit to develop a perturbative approach valid for weak feedback. We show that through this method we can extract the full counting statistics of the signal, the quantum-classical mutual information between the system and signal, and the Fisher information of the signal, which can be used for sensing applications. Our results are illustrated with both single-qubit models and the spin chains governed by the one-dimensional transverse field Ising model or the Lipkin-Meshkov-Glick model.
Description
Keywords
Deterministic approach , Filtered signals , Fisher information matrix , Fokker Planck , Fokker Planck equation , Full counting statistics , Master equations , Perturbative approach , Quantum optics , Quantum system , Quantum-classical , Qubits , Signal processing , Signals statistics , Steady state , [Physics]
Citation
Kiely, A & Landi, G 2026, 'Extracting filtered signal statistics of continuously measured quantum systems', Physical Review A, vol. 113, no. 3, 032442, pp. 1-12. https://doi.org/10.1103/yxqg-93jz