Stark位移对混态J-C模型中熵和纠缠的影响  

Influence of Stark shift on entropy and entanglement in J-C model with mixed states

作　　者：胡要花[1] 

机构地区：[1]洛阳师范学院物理与电子信息学院,河南洛阳471022

出　　处：《量子电子学报》2012年第4期441-447,共7页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金青年基金(10905028);河南省科技计划(102300410050)资助项目

摘　　要：考虑一个二能级原子与单模热光场经由双光子过程耦合,采用量子约化熵研究了原子和场的约化熵变化规律,用共生纠缠度(Concurrence)研究了原子与场之间的纠缠演化。借助于数值计算方法,详细分析了在混态J-C模型中,Stark位移和平均光子数对约化熵变和纠缠的影响。结果表明在Stark位移影响下,原子和光场的约化熵变化量均减小。选择适当的原子初态,可以使得原子的约化熵和光场的约化熵发生交换。此外,考虑Stark位移时,原子与光场之间纠缠的最小值增大,原子与光场不再出现退纠缠态。A two-level atom coupling with a single-mode thermal field through two-photon processes is considered.The reduced entropy change of the atom and field was studied by using quantum reduced entropy,and entanglement between the atom and field was measured by using concurrence.By means of numerical computation method,the effect of the Stark shift and mean photon number in J-C model with mixed states on the reduced entropy change and entanglement was investigated.The results show that reduced entropy changes of the atom and field decrease under the influence of Stark shift.When the initial parameters are suitable,the complete exchange between the atomic and field reduced entropy occurs.In addition,the minimum values of the entanglement raise in the presence of Stark shift,which means that the atom is no longer disentangled from the field.

关 键 词：量子光学 纠缠 共生纠缠度 量子约化熵 STARK位移 JAYNES-CUMMINGS模型 

分 类 号：O431.2[机械工程—光学工程]