超薄磁膜磁特性的Heisenberg模型分析

应用ＭｏｎｔｅＣａｒｌｏ方法,研究了交换相互作用、表面各向异性和长程偶极相互作用共同作用下的超薄磁膜的磁特性。通过计算不同参数下系统的温度效应,分析了各种相互作用对系统状态的不同影响。在此基础上,通过分析自旋垂直分量绝对值等序参量的变化特征,发现在适当参数时,系统自旋通过温度效应可越过垂直取向和平面取向间的势垒,从而发生从垂直磁化向面内磁化的转变。

Analysis of the magnetic properties in ultrathin films by Heisenberg model

In this paper, by using Monte Carlo simulations, we have studied the magnetic properties of the ultrathin films with the surface anisotropy, long-ranged dipole interaction and short-ranged exchange interaction. Through the calculation of the temperature effect in different parameters, the different influences of various interactions on the behaviors of the system are theoretically analyzed. On the basis of these analyses, by studying the features of the absolute values of the perpendicular component of the spin, it is found that the reorientation transition from an out-of-plane phase to an in-plane phase can occur when the spins get across the potential barrier between the out-of plane and the in-plane ordered state through the effects of the temperature under the suitable parameters.