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

TL;DR

This paper explores how quantum Zeno and anti-Zeno effects influence the entanglement dynamics of qubits in a non-Markovian environment, revealing conditions under which entanglement can be protected or enhanced through measurements.

Contribution

It provides analytical expressions for entanglement evolution under Zeno and anti-Zeno effects in non-Markovian settings, considering system size, detuning, and coupling regimes, which was not previously detailed.

Findings

Detuning can protect entanglement in weak coupling.

Zeno effect dominates when detuning is less than cavity damping.

Anti-Zeno effect can enhance entanglement in strong coupling.

Abstract

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