低能原子簇轰击金属簿膜引起的级联碰撞(Ⅱ)——注入簇原子的加速

研究了能量为１ｋｅＶ／ａｔｏｍ的金原子簇和０．２ｋｅＶ／ａｔｏｍ的铝原子簇轰击金薄膜产生的级联碰撞。用分子动力学模拟计算了注入靶后的簇原子能量分布及其随时间的演化。结果表明，在原子簇注入引起的级联碰憧中，簇原子除了将能量传递给靶原子外，尚有可能破加速。簇原子的最高能量可大于它的初始能量；分析了原子簇注入引起的多次碰撞效应，并用经典力学守恒定律计算了一个簇原子发生二次散射后的能量增益，用以解释注入原子的加速机制。 关键词：

COLLISION CASCADES INDUCED BY LOW ENERGY CLUSTERS IMPACTING ON METALLIC THIN FILMS (II)——THE ACCELERATION OF CLUSTER ATOMS

This paper present the investigation on collision cascades induced by gold clusters at 1keV/atom and aluminum clusters at 0.2keV/atom impacting on gold thin films. The energy spectra of projectiles at different time are calculated by molecular dynamics simulations. It is shown that the cluster atoms may even be accelerated during the slowing down process. The maximum energy of cluster atoms is found to be higher than their initial energy. In order to understand the acceleration mechanism, multiple collision processes have been studied. The possible energy gains of a cluster atom after double scatterings are calculated by the classical conservation laws.