Quantum Zeno and Anti-Zeno Effects on the Entanglement Dynamics of Qubits Dissipating into a Common and non-Markovian Environment

摘要

We investigate the quantum Zeno and anti-Zeno effects on pairwiseentanglement dynamics of a collective of non-interacting qubits which have beeninitially prepared in a Werner state and are off-resonantly coupled to a commonand non-Markovian environment. We obtain the analytical expression of theconcurrence in the absence and presence of the non-selective measurements. Inparticular, we express our results in the strong and weak coupling regimes andexamine the role of the system size, and the effect of the detuning from thecavity field frequency on the temporal behaviour of the pairwise entanglement.We show that, the detuning parameter has a positive role in the protection ofentanglement in the absence of the measurement for weak coupling regime. Wefind that for the values of detuning parameter less than the cavity dampingrate, the quantum Zeno effect is always dominant, while for the values greaterthan the cavity damping rate, both Zeno and anti-Zeno effects can occur,depending on the measurement intervals. We also find that the anti-Zeno effectcan occur in the pairwise entanglement dynamics in the absence and presence ofthe detuning in the strong coupling regime.