Dynamics of Quantum Fisher Information in Homodyne-Mediated Feedback Control
Li Chen1,2**, Dong Yan1,2, Li-Jun Song2,3, Shou Zhang4
1School of Science, Changchun University, Changchun 130022 2Key Laboratory of Materials Design and Quantum Simulation, Changchun University, Changchun 130022 3School of Information Engineering, Jilin Engineering Normal University, Changchun 130052 4Department of Physics, College of Science, Yanbian University, Yanji 133002
Abstract：We investigate the quantum Fisher information (QFI) dynamics of a dissipative two-level system in homodyne-mediated quantum feedback control. The analytical results demonstrate that the maximum values and stable values of the QFI can be greatly enhanced via feedback control. The quantum feedback plays a more evident role in the improvement of classical Fisher information. The classical part can reach a high stable value, while the quantum part eventually decays to zero whatever the feedback parameter is.
2019, Vol. 36 
