好腔中的Bell态原子与纠缠相干态光场相互作用系统的保真度  

The fidelities of quantum states in the system of the two-mode entangled coherent field interacting with atoms in Bell states for fine cavity

作　　者：章国顺[1,2] 杨名[2] 曹卓良[2,3] 曹春斌[1] 

机构地区：[1]安徽农业大学理学院,合肥230036 [2]安徽大学物理与材料科学学院,合肥230039 [3]合肥师范学院物理系,合肥230061

出　　处：《原子与分子物理学报》2008年第5期1287-1293,共7页Journal of Atomic and Molecular Physics

基　　金：国家青年自然科学基金(10704001);安徽省自然科学基金(070412060);安徽省高校自然科学基金(JK2008B015)

摘　　要：考虑原子间偶极相互作用，求出好腔中的Bell态原子与纠缠相干态光场相互作用系统的保真度。结果表明，对于理想腔，若原子初始时刻处于相干保持态，系统保真度始终等于1；若原子初始时刻处于其余Bell态之一，腔场初态的平均光子数很小，系统保真度在0～1之间作周期性振荡，随着腔场初态的平均光子数的增加，系统保真度的振荡频率增大，振幅减小。对于好腔，若原子初始时刻处于相干保持态，系统保真度呈指数单调衰减；若原子初始时刻处于其余Bell态之一，系统保真度呈指数振荡衰减，且随着腔场初态的平均光子数的增加，系统保真度的振荡频率增大，振幅减小。Interaction between two atoms is considered. The fidelities of quantum states in the system of the two-mode entangled coherent field interacting with atoms in Bell states are derived. The results indicate that for ideal cavity, the fidelity of the system always equals to one for the coherent maintenance state at original time. The fidelities of the system surge periodically from 0 to 1 for the etceteras Bell state at original time when average photon number of two-mode entangled coherent states cavity fields are very small. When average photon number of two-mode entangled coherent states cavity fields increase, oscillatory frequency of the fidelities of the system augments and swing decrease. For fine cavity, the fidelity of the system is humdrum exponent attenuation for the coherent maintenance state at original time. The fidelities of the system are oscillatory exponent attenuation for the etceteras Bell state at original time, and when average photon number of two-mode entangled coherent states cavity fields increase, oscillatory frequency of the fidelities of the system augments and swing decrease.

关 键 词：量子光学 保真度 BELL态 纠缠相干态光场 好腔 

分 类 号：O431.2[机械工程—光学工程]