Co2YSn(Y=Ti,Zr)电子结构和轨道磁性的第一性原理研究

基于密度泛函理论(DFT)采用第一性原理的全势能线性缀加平面波(FLAPW)的能带计算方法研究了强磁性Heusler合金Co2TiSn和Co2ZrSn的电子能带结构,在计算中考虑了自旋-轨道藕合(SOC)的修正.计算结果表明两种合金在费米面附近的能带结构是一个d-d电子杂化作用形成的能带.分析计算结果发现Co原子对磁矩有主要的贡献,两种Heusler合金的磁矩是由于Co原子3d eg的自旋劈裂形成的,3deg的自旋向下分量是合金的电子态密度(DOS)的主要来源.由能带计算得到Co2TiSn和Co2ZrSn的自旋磁矩分别为1.97μB和1.96μB,其中Co原子在上述两种合金中的自旋磁矩分别是1.01μB和1.02μB,轨道磁矩分别为0.041μB和0.051μB.     

Modelling of an obliquely deposited thin film in three dimensions by kinetic Monte Carlo method

A simulation of the growth of an obliquely deposited thin film in a three-dimensional lattice was made using kinetic Monte Carlo method. Cu growth in three dimensions on a (001) substrate with high deposition rates has been simulated in this model. We mainly investigated the variation of three-dimensional morphology and microstructure offilms with incidence angle of sputtered flux. The relation of roughness and densities of films with incidence angle was also investigated. The simulation results show that the surface roughness increases and the relative density of thin film decreases with increasing incidence angle, respectively; the columnar structures were separated by void regions for large incidence angle and high deposition rate. The simulation results are in good agreement with experimental results.However, the orientation angle of columns is not completely consistent with the classical tangent rule.     

基于Matlab GUI的拉伸法测杨氏弹性模量实验的数据处理

借助Matlab软件分别采用逐差法和最小二乘法对拉伸法测量杨氏弹性模量实验进行数据处理，利用Matlab GUI设计数据处理交互式界面，通过在GUI界面输入测量数据和实验参数，绘制出了拟合直线图，实现了杨氏模量值及其不确定度的程序计算，分析了两种方法求得的实验结果。数据处理过程操作简单，提高了学生运用软件的能力和实验效率。