混合态下运动原子与相干态光场相互作用的量子纠缠  

Quantum entanglement of the coherent field interacting with the moving atom being in a mixed state

作　　者：李红星[1] 萨楚尔夫[1,2] 冯川[1] 张冬霞 

机构地区：[1]内蒙古师范大学物理与电子信息学院,呼和浩特010022 [2]内蒙古师范大学图书馆,呼和浩特010022 [3]内蒙古乌海市第一中学,乌海市016000

出　　处：《原子与分子物理学报》2013年第5期791-797,共7页Journal of Atomic and Molecular Physics

基　　金：内蒙古自然科学基金项目(2013MS0115);内蒙古师范大学"十百千"人才工程基金项目

摘　　要：利用负熵方法,研究了混合态运动原子与相干态光场相互作用系统的量子纠缠特性,讨论了原子初态、场模结构参数、相干场平均光子数、失谐量、跃迁光子数等物理参量对系统纠缠度的影响.结果表明:考虑原子运动时,系统纠缠度在整个时域范围内出现了规则的周期振荡.原子初态趋于纯态时系统纠缠度较高.随着相干场平均光子数的增大,系统纠缠度的峰值逐渐变小,规则振荡的周期不变.随着跃迁光子数的增大,系统纠缠度的峰值逐渐变大,振荡变得越来越快.随着失谐量的增大,系统纠缠度的峰值逐渐变小.Using the negative entropy method, the quantum entanglement character of the system of the coherent optical field interacting with the moving atom is studied. The influences of the atomic initial state, the field-mode structure parameter, the average photon number of the coherent field, the detun- ing, and the transition photon number on the entanglement character of the system are discussed. The result shows that the value of the entanglement degree of the system appears regular evolution and en- tanglement sudden death phenomenon （ESD） when the atomic motion is considered. When the atomic initial state tends to pure state, the entanglement degree of the system is larger relatively. With the in- crease of the average photon number of the coherent field, the value of the entanglement degree of the system becomes small, but the period for the regular evolution is almost unchanged. With the increase of the transition photon number, the value of the entanglement degree of the system becomes larger, the period of the oscillation becomes shorter, meanwhile the oscillation of the system becomes faster and fas- ter. With the detuning increasing,the entanglement becomes small.

关 键 词：量子光学 量子纠缠 相干光场 混合态 

分 类 号：O431.2[机械工程—光学工程]