论文标题
将电子停止的包含和验证在开源LAMMPS代码中
Inclusion and validation of electronic stopping in the open source LAMMPS code
论文作者
论文摘要
在模拟碰撞级联时，无法通过用于分子动力学（MD）模拟中使用的原子间电位来照顾能量原子的电子停止（ES）。因此，将用于电子停止的Lindhard-scharff（LS）公式作为开源大规模原子中的能量原子的阻力术语包括在内。为了验证ES实施，在100个随机方向上，在W和FE中对5、10和20 keV进行碰撞级联对5、10和20 keV的MD模拟。 MD模拟的总ES损失显示由于现象的随机性而引起的能量散落。将由于ES引起的Thelosses与Thenorgett-Robinson-Torrens（NRT）模型的预测相提并论，以验证我们的实现。与NRT模型相比，W与MD实现的ES损失与MD实施的均方根损失的均方根均值约为10 \％。探索了电子停止很重要的速度阈值。 ES对FE和W的碰撞级联反应次数的影响。
Electronic stopping (ES) of energetic atoms is not taken care of by the interatomic potentials used in molecular dynamics (MD) simulations when simulating collision cascades. The Lindhard-Scharff (LS) formula for electronic stopping is therefore included as a drag term for energetic atoms in the open source large scale atomic molecular massively parallel simulator (LAMMPS) code. In order to validate the ES implementation, MD simulations of collision cascades at primary knock-on atom (PKA) energies of 5, 10 and 20 keV are carried out in W and Fe in 100 random directions. The total ES losses from the MD simulations show energy straggling due to the stochastic nature of the phenomena. Thelosses due to ES are compared with that predicted by theNorgett-Robinson-Torrens (NRT) model to validate our implementation. It is seenthat the root mean square deviation of ES losses from the MD implementation is around 10 \% for both W and Fe compared to the NRT model. The velocity threshold above which electronic stopping is important is explored. The effect of ES on the number of defects in collision cascades is presented for Fe and W.
