光电子全息的计算机模拟和数值重现

SIMULATION AND NUMERICAL RECONSTRUCTION OF PHOTOELECTRON HOLOGRAPHY

Ｘ射线被原子的芯能级吸收后，激发产生的光电子波在传播过程中被周围的原子散射，同源产生的带有周围原子结构信息的散射波（物波）与未被散射的光电子波（参考波），具有良好的相干性，这两列波的衍射图即是光电子全息图。通过重现全息图，可重构三维空间原子像，获得原子级分辨率的三维结构信息。采用合理的物理模型，对ｃ（２×２）Ｓ／Ｎｉ表面中Ｓ原子、金属Ｃｕ原子以及ＹＢＣＯ原胞中的Ｃｕ２原子近邻的一些原子簇，进行了光电子全息产生过程的计算机模拟。全息重现则采用数值重现的方法。

Photoelectron outgoing wave emitted from core state o f excited atom will be scattered by near neighbor atoms.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 photoelectron hologram,will b e created.A complete 3 D image of the structure surrounding the emitter with at omic resolution can be reconstructed.This paper gives computer simulation for ca lculat ing photoelectron holograms of small atomic clusters on c(2×2)S/Ni(100) surfac e,in metal copper,and on puckered Cu2O plane of superconductor YBCO.