利用全量子理论及部分转置矩阵负本征值的方法,研究了存在相位退相干时多光子T-C模型中 两个二能级原子与数态光场相互作用系统中两原子的纠缠演化特性。讨论了相位退相干系数、 原子间偶极-偶极相互作用系数、跃迁光子数对原子间纠缠演化特性的影响。结果表明:相位退相干 因子并不能完全破坏两原子间的相干性,而是衰减了原子间纠缠度的振荡幅度。随着偶极相互作用系 数的增大和跃迁光子数的增多,两原子最终处于纠缠度值较稳定的纠缠态;两纠缠原子相干性越好, 两原子越容易达到纠缠度值较大且稳定的纠缠态。

By means of the quantum theory and negative eigenvalues of the partial transposition, properties of entanglement evolution in system of two two-level atoms coupled to a light field in the Fock state are investigated in the presence of phase decoherence in the multiphoton Tavis-Cumming Model. The influences of the phase decoherence coefficient, dipole-dipole coupling intensity and number of transitional photons on properties of entanglement evolution between two atoms were discussed. The results show that the phase decoherence doesn’t destroy coherence completely but attenuates oscillated amplitude of the entanglement degree between two entangled atoms. With increasing of the dipole-dipole coupling intensity and number of transitional photons, the two entangled atoms approach the entanglement state in which there is a stable entanglement degree finally. The better coherences between two atoms are, the larger value of entanglement degree between two entangled atoms can be obtained, and state in the two entangled atoms are more stable.