【摘要】 利用在国家同步辐射实验室建立的光电子衍射技术 ,采集了GaAs(0 0 1 )面能量扫描的光电子衍射谱。通过对光电子衍射谱的傅立叶变换分析给出了各个发射体近邻原子的正确位置 .经过多重散射模型计算并对实验曲线的拟合验证了Biegelsen提出的Ga双层模型的正确性 .结果显示 ,最外层构成二聚体的两个Ga原子沿 [1 1 0 ]方向移动聚拢 ,偏离体材料格位 8.3% .同时最外层的Ga原子向内收缩 2 .1 % .更多还原

【Abstract】 The photoelectron diffraction (PD) curves of GaAs(001) surface are obtained by energy scan mode based on the PD technique set up in National Synchrotron Radiation Laboratory (NSRL). The correct atom positions near each emitter are given by analyzing the Fourier transform of PD curves. The fitting of experimental curves by using the calculation of multiple scattering models confirms the ‘Ga bi layer’ model proposed by Biegelsen. The results show that two adjacent outmost Ga atoms (dimmer) move close together to form an 8.3% deviation from the bulk site. And the outmost Ga dimmers relax inward 2.1%.更多还原