相位退相干对多光子过程中两原子纠缠的影响  

Influence of phase decoherence on entanglement of two atoms in multiphoton process

作　　者：张冬霞[1] 萨楚尔夫[1,2] 牧其尔[1] 

机构地区：[1]内蒙古师范大学物理与电子信息学院,内蒙古呼和浩特010022 [2]内蒙古师范大学图书馆,内蒙古呼和浩特010022

出　　处：《量子电子学报》2011年第4期439-445,共7页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金资助项目(60467002);内蒙古自然科学基金资助项目(2009MS0112);内蒙古高等学校科研基金项目(NJ03038);内蒙古师范大学研究生科研基金项目(CXJJS10036)

摘　　要：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.

关 键 词：量子光学 纠缠特性 部分转置矩阵负本征值 相位退相干因子 

分 类 号：O431.2[机械工程—光学工程]