Quantum correlations and quantum Fisher information of two qubits in the presence of the time-dependent coupling effect

• Published in: European physical journal plus Vol. 135; no. 6; p. 467
• Main Authors: Raffah, Bahaaudin, Abdel-Khalek, S., Berrada, K., Khalil, E., Al-Hadeethi, Yas, Almalky, Nawal, Wahiddin, M. R. B.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2020; Springer Nature B.V
• Subjects: Applied and Technical Physics; Atomic; Complex Systems; Condensed Matter Physics; Correlation; Coupling; Dissipation; Eigenvalues; Entropy; Fisher information; Information technology; Investigations; Mathematical and Computational Physics; Molecular; Optical and Plasma Physics; Parameter estimation; Physics; Physics and Astronomy; Quantum entanglement; Qubits (quantum computing); Regular Article; Theoretical; Time dependence
• ISSN: 2190-5444; 2190-5444
• DOI: 10.1140/epjp/s13360-020-00423-7

In this paper, we consider two separate Jaynes–Cummings (JC) nodes with a nonidentical qubit-field system in the presence of dissipation terms. We reveal the influence of the time variation of the coupling terms on some important measures when the qubits are immersed in a vacuum. The density matrix for the two qubits initially in Bell states are obtained. The dynamical behavior of the quantum discord (QD), classical correlation (CC), qubit-qubit entanglement, and quantum Fisher information (QFI) is investigated. We explore the relationship among QD, CC, qubit-qubit entanglement, and QFI in the absence and presence of the dissipation effect during the time evolution. Furthermore, we show the main optimal conditions for obtaining a high level of correlation and coherence between the two qubits.