【摘要】 用两个自旋相互垂直的s=1的层状伊辛模型描述磁性薄膜极化转向的物理过程 .计算了自由能密度随原子层的增加所发生的变化 ,得到了与实验定性相同的极化方向转变的规律 .结果显示 :在层数增加过程中 ,偶极作用的影响基本保持不变 ,发生极化转向的主要原因是表面垂直各向异性能的影响随层数增加被逐渐削弱 ,最终弱于偶极作用的影响而导致极化方向从垂直转到平行膜面 .更多还原

【Abstract】 The competition between dipole\|dipole interaction and surface anisotropy in a thin ferromagnetic film is described by two spin \%s\%=1 layered Ising systems.The spin is perpendicular to the layers in one system,and is in\|plane in the other system.Free energy densities in the two systems are calculated by use of VCE method.The results show that the magnetization will transfer from perpendicular to in\|plane when the number of layers increase.In this process,the influence of dipole\|dipole interaction which favors the in\|plane magnetization is approximately a constant and that of surface anisotropy which favors the perpendicular magnetization decreases apparently.Finally the dipole\|dipole interaction prevails over the surface anisotropy,and then the reorientation transition occurs.更多还原