The entanglement properties of a single-mode vacuum field interacting with a pair of atoms are investigated by using the quantum reduced entropy,and the influences of the atomic dipole-dipole interaction on the degree of the entanglement are discussed.
The entanglement properties of the system of two two-level atoms interacting with a single-mode vacuum field are explored. The quantum entanglement between two two-level atoms and a single-mode vacuum field is investigated by using the quantum reduced entropy; the quantum entanglement between two two-level atoms and that between a single two-level atom and a single-mode vacuum field are studied in terms of the quantum relative entropy. The influences of the atomic dipole–dipole interaction on the quantum entanglement of the system are also discussed. Our results show that three entangled states of two atoms–field, atom–atom and atom–field can be prepared via two two-level atoms interacting with a single-mode vacuum field.
We investigate the entanglement in a system of two coupling atoms interacting with a single-mode field by means of quantum information entropy theory. The quantum entanglement between the two atoms and the coherent field is discussed by using the quantum reduced entropy, and the entanglement between the two coupling atoms is also investigated by using the quantum relative entropy. In addition, the influences of the atomic dipole–dipole interaction intensity and the average photon number of the coherent field on the degree of the entanglement is examined. The results show that the evolution of the degree of entanglement between the two atoms and the field is just opposite to that of the degree of entanglement between the two atoms. And the properties of the quantum entanglement in the system rely on the atomic dipole–dipole interaction and the average photon number of the coherent field.
The entanglement dynamics of two partially entangled two-level atoms interacting with a single mode vacuum field is investigated.The entanglement dynamics between two partially entangled two-level atoms and the vacuum field is explored by using the quantum re- duced entropy,and that between two two-level atoms is studied by using the quantum relative entropy.The influences of the atomic dipole-dipole interaction intensity on the entanglement dynamics of the system are also discussed.The results show that the system exhibits periodic entanglement dynamics,and the magnitude and the period of entanglement depend on the atomic dipole-dipole interaction.The atom-field maximal entanglement state and atom-atom maximal entanglement state can be preparated by selecting appropriate system parameters and the interaction time.
The properties of quantum field entropy evolution in a single-mode vacuum field-coupled two-level atoms′ system were by the complete quantum theory.The numerical results indicate that the quantum field entropy in the system is periodic oscillation with two peaks′ or many peaks′ structures;The quantum entanglement between the atoms decreases with the increase of the dipole-dipole interaction strength between them;The amplitude of the field quantum entropy decreases with the increase of the probability of the two atoms stayed simultaneously in their ground states;Especially when the two atoms both stayed in their ground states,the field and the atoms are both disentangled for a long time;The coupling strength between the field and the atoms has important influences on the periodicity of the field quantum entropy,namely,the periodicity mentioned above becomes shorter with the strengther of the coupling.
The entanglement degrees of two coupling-atoms interacting with a single-mode vacuum field in the Tavis-Cummings model were investigated by using quantum relative entropy.The influence of the dipole-dipole interaction between atoms on the entanglement degrees of the relative entropy was discussed.The results indicated that the entanglement degrees of atom-atom and atom-field evolved periodically with the antiphase.The increase of the atomic dipole-dipole coupling led to the increase of evolution period,the constant of atom-atom entanglement degree while the decrease of atom-field entanglement degree.