Entanglement and entropy squeezing in the system of two qubits interacting with a two-mode field in the context of power low potentials

E M Khalil,A Al-Barakaty,J Peřina,K Berrada,S Abdel-Khalek

doi:10.1038/s41598-020-76059-5

Abstract

We study the dynamics of two non-stationary qubits, allowing for dipole-dipole and Ising-like interplays between them, coupled to quantized fields in the framework of two-mode pair coherent states of power-low potentials. We focus on three particular cases of the coherent states through the exponent parameter taken infinite square, triangular and harmonic potential wells. We examine the possible effects of such features on the evolution of some quantities of current interest, such as population inversion, entanglement among subsystems and squeezing entropy. We show how these quantities can be affected by the qubit-qubit interaction and exponent parameter during the time evolution for both cases of stationary and non-stationary qubits. The obtained results suggest insights about the capability of quantum systems composed of nonstationary qubits to maintain resources in comparison with stationary qubits.

Highlights

We study the dynamics of two non-stationary qubits, allowing for dipole-dipole and Ising-like interplays between them, coupled to quantized fields in the framework of two-mode pair coherent states of power-low potentials
“Measures and numerical results”, we present the numerical results of the possible effects of such features on the evolution of some quantities of current interest, such as population inversion, entanglement among subsystems and squeezing entropy
We have introduced a useful model describing the dynamics of two nonstationary qubits, allowing for dipole–dipole and Ising-like interplays between them, coupled to quantized fields in the framework of twomode pair coherent states of power-low potentials

Summary

Physical model

Let the Hamiltonian model of the system under study be described as follows:. HAI = D σ+(A)σ−(B) + σ−(A)σ+(B) + SσZ(A)σZ(B). In order to observe how the dipole-dipole and Ising interactions affect on the time variation of the qubits-field entanglement, clearly, in Fig. 4, we show the time evolution of function SAB(t) with respect to different values of the model parameters. After adding dependence on time, the previous chaotic oscillations become more uniform and the maximum values of NAB(t) decrease In order to examine the dynamical behavior of the entropy squeezing of the qubit system in the presence of the qubit–qubit interaction, the time evolution of the entropies EX and EY versus the dimensionless quantity ǫt is displayed in Fig. 8 with respect to different values of the physical parameters of the model. The existence of these parameters decrease the effect of the qubit–field coupling parameter on the behavior of the entropies

Conclusion

Additional information