通过计算并发度和线性熵研究了单光子和双光子Jaynes-Cummings模型中两原子系统的纠缠随时间的演化特性，分析了原子初始纠缠度和不同腔场初态对并发度的影响。结果表明，当腔场初始处于|11〉态时，两原子之间的纠缠出现突然死亡现象，纠缠死亡的持续时间依赖于原子初始纠缠度；并且发现两原子和腔场之间在整个时间演化过程中一直保持着纠缠状态。

The entanglement dynamics of two atoms in the one-photon and two-photon Jaynes-Cummings models are studied by employing the concurrence and linear entropy. The effect of the initial entanglement degree of two atoms and the initial state of the cavity field on the time evolution of concurrence is analyzed. The results show that the phenomenon of sudden death of entanglement between two atoms happens when the field is initially in the state |11〉. The length of the death time interval is dependent on the initial entanglement degree of two atoms. Moreover, it is found that the atom and the field are entangled in the overall time evolution process.