Entanglement dynamics of bipartite system in squeezed vacuum reservoirs

TL;DR

This paper investigates how entanglement in a two-qubit cavity system evolves when interacting with squeezed vacuum reservoirs, revealing conditions for entanglement preservation and the impact of reservoir parameters on entanglement sudden death.

Contribution

It introduces a scheme for directly measuring entanglement in cavity-QED systems and analyzes the effects of squeezed vacuum reservoirs on entanglement dynamics, including sudden death phenomena.

Findings

Entanglement can be maintained under certain conditions despite reservoir interaction.

The time of entanglement sudden death depends on initial states and reservoir parameters.

A direct measurement scheme for entanglement in cavity-QED systems is proposed.

Abstract

Entanglement plays a crucial role in quantum information protocols, thus the dynamical behavior of entangled states is of a great importance. In this paper we suggest a useful scheme that permits a direct measure of entanglement in a two-qubit cavity system. It is realized in the cavity-QED technology utilizing atoms as fying qubits. To quantify entanglement we use the concurrence. We derive the conditions, which assure that the state remains entangled in spite of the interaction with the reservoir. The phenomenon of sudden death entanglement (ESD) in a bipartite system subjected to squeezed vacuum reservoir is examined. We show that the sudden death time of the entangled states depends on the initial preparation of the entangled state and the parameters of the squeezed vacuum reservoir.