摘要
原子的芯能级电子吸收能量后被激发 ,经过退激发过程发射出的俄歇电子波在传播过程中被周围的原子散射 ,带有周围原子结构信息的散射波 (物波 )与未被散射的电子波 (参考波 )相干涉形成的衍射图即俄歇电子全息图 ,通过全息图的重现 ,可获得原子级分辨率的三维结构信息。本文在合理的物理模型下 ,以Cu单晶以及高温超导YBCO中的Y原子近邻的一些原子簇为计算实例 ,首次就受激原子周围单层近邻原子散射和多层原子散射产生的俄歇电子全息进行了计算机模拟和数值重现 ,获得了三维晶格结构参量 ,并讨论了不同原子序数的原子在全息图形成及重现中的作用。
The excited Auger electron wave emitted from core state of excited atom will be scattered by near neighbor atoms in the way of its propagating.Scattered waves (object waves) which contain structural information of the environment around the excited atom interfere with the original one (reference wave) which propagates directly to the detector and then a diffraction pattern,i.e.a Auger electron hologram,will be created.A complete 3 D image of the structure surrounding the emitter with atomic resolution can be reconstructed.The small atomic clusters in metal copper and in superconductor YBCO were used for simulating examples of Auger electron holography.The 3 D structural parameters of sample can be accurately obtained by numerical reconstruction of Auger electron hologram.The effect of scattered atoms with different atom number in creating hologram is also discussed.
出处
《真空科学与技术》
CSCD
北大核心
2000年第4期264-269,共6页
Vacuum Science and Technology
基金
上海市教委重点学科基金项目
上海市应用物理研究中心资助项目
关键词
俄歇电子全息
电子散射
计算机模拟
材料微结构
Auger electron holography,Electron wave scattering,Computer simulation,Numerical reconstruction
