We investigate entanglement dynamics for two atoms coupling with fluctuating electromagnetic field in the cosmic string spacetime. We calculate the entanglement for different conditions. It is found that the entanglement behaviors are dependent on vacuum fluctuation, spacetime topology, two-atom separation and atomic polarization orientation. After a long time of evolution, entanglement would vanish, which means entanglement affected by electromagnetic fluctuation cannot maintain for a long time. For different spacetime topologies, entanglement presents different behaviors dependent on various parameters. When deficit angle parameter \(\nu =1\) and atom–string distance is toward infinity, the results in flat spacetime are recovered. When atoms keep close to the string, entanglement can be improved; specially, when two atoms locate on the string and have no polarization of axial direction, atoms are not affected by the electromagnetic fluctuation and entanglement can remain unchanged. When two-atom separation is relatively large, entanglement exhibits oscillation behavior as atom–string distance varies. This indicates that the existence of string profoundly modifies on the vacuum fluctuation and atom–field interaction. In addition, when two-atom separation is small, entanglement gains better improvement. Many parameters and conditions provide us with greater freedom to control the entanglement behaviors. In principle, this is useful to sense the cosmic string spacetime topology structure and property and discriminate different kinds of spacetime.

我们研究宇宙弦时空中两个原子与波动电磁场耦合的纠缠动力学。我们计算不同条件下的纠缠度。发现纠缠行为取决于真空起伏，时空拓扑，两原子分离和原子极化取向。经过长时间的发展，纠缠将消失，这意味着受电磁波动影响的纠缠无法长期维持。对于不同的时空拓扑，取决于各种参数，纠缠表现出不同的行为。当亏角参数\（\ nu = 1 \）并且原子串的距离接近无穷大，恢复了平坦时空的结果。当原子靠近弦时，缠结会得到改善；特别地，当两个原子位于弦上并且没有轴向极化时，原子不受电磁波动的影响，并且缠结可以保持不变。当两原子分离相对较大时，随着原子串距离的变化，纠缠会表现出振荡行为。这表明，串的存在极大地改变了真空涨落和原子-场相互作用。另外，当两个原子的分离较小时，缠结会得到更好的改善。许多参数和条件为我们提供了更大的自由来控制纠缠行为。原则上，