Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

Abstract

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, {\color{blue}suprisingly} these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. {\color{blue} Here, we aim to show that how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum resources.} To do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. {\color{blue} In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement (BSM) is performed on the output of the system to quantify the entanglement and coherence. } The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental effects. Nevertheless, the local coherence may show the same behavior as the remote coherence. {\color{blue} Besides, the system provides the steady state entanglement in various interaction regimes, particularly in the strong atom-cavity coupling and with the relatively large detuning. More interestingly, our numerical analyses demonstrate that the system may show memory effect due top the fact that the death and revival of entanglement take place during the interaction.} Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication. \\