Stark位移对热环境下双Jaynes-Cummings模型中原子纠缠的影响

研究双光子跃迁的双Jaynes-Cummings模型中, 两原子初始处于最大纠缠态、光场初始处于单模热态时的原子纠缠动力学, 考虑双光子过程中的Stark位移、热光场的平均光子数对原子纠缠的影响. 结果表明: 不考虑Stark位移时, 两原子在系统演化过程中周期性地出现退纠缠现象, 而考虑Stark位移时, 两原子长时间地纠缠. 特别是当Stark位移参数取值较大且热光场的平均光子数值比较小时, 两原子能保持 稳定地纠缠. 这些结果表明, 可以利用Stark位移对热环境下双Jaynes-Cummings模型中的原子纠缠进行调控.

Effect of the Stark shift on entanglement in a double Jaynes-Cummings model in thermal environment

Considering a double two-photon Jaynes-Cummings (J-C) model, we study the effects of Stark shift and mean photon number on entanglement between two two-level atoms when the atoms are initially in a maximally entangled state and the fields are in the single-mode thermal fields. The results show that the two atoms evolve periodically into a disentangled separable state when Stark shift is not considered. However, in the presence of Stark shift, the two two-level atoms are no longer disentangled and long-lived entanglement can be obtained. For a larger value of the Stark shift parameter and a smaller mean photon number, the two atoms can remain in a stationary entangled state. These properties show that the Stark shift can be used to control entanglement in the double two-photon J-C model under the influence of thermal environment.