Anomalous Ion Acceleration Mechanism in Intense Laser-Irradiated Graphene

这项研究的动机是确定反常加速机制，由于这种机制，当超强激光照射时，只有超薄的石墨烯目标才会产生极高能量的碳离子。假设激光预脉冲改变了靶的结构，从而影响了离子加速。然而，没有预先存在的方法来检验这一假设。因此，我们提出了一种混合模拟方案，利用分子动力学(MD)模拟对预脉冲进行建模，然后结合电磁(EM)等离子体模拟为主脉冲。在2022财年，我们成功地创建了结合MD和EM模拟的混合模拟。对该模拟的验证研究表明，该模拟与先前的实验吻合良好。

The motivation of this research is to identify the anomalous acceleration mechanism due to which, extremely high energy carbon ions are generated only from an ultra-thin graphene target, when irradiated with an ultra-intense laser. The hypothesis was that the laser prepulse modifies the target structure thus affecting the ion acceleration. However, there were no pre-existing methods to test this hypothesis. Hence, we proposed a hybrid simulation scheme where the prepulse is modeled using molecular dynamics (MD) simulation and then combined with electromagnetic (EM) plasma simulation for the main pulse. Over the FY2022, we succeeded in creating a hybrid simulation that combines MD and EM simulations. The validation study for this simulation showed good agreement with a previous experiment.