量子点磁化动力学行为的研究

Study of Magnetic Dynamic Properties for Quantum Dots

利用Monte-Carlo方法研究磁性量子点阵列在不同交换耦合常数Jex、偶极相互作用常数D和磁各向异性常数K下的磁化曲线及自旋组态.模拟结果表明,对于不同的Jex和D,系统表现出不同的磁化行为和自旋组态;当Jex=0.0,D取小值时,量子点阵列的磁性基本保持了孤立原子团的磁特性,矫顽力随温度变化关系与单个的磁性原子团的相似,在低温区,矫顽力随温度的增加急剧减少;在中间温区,出现矫顽力极小;在更高温区,矫顽力随温度的增加而减少.

Base on the Monte-Carlo simulation,the effect of exchange interaction constant Jex,dipolar interaction constant D and magnetic anisotropy constant K on magnetization curves,spin configuration of quantum dots are studied.It is found that the system displays different magnetization behavior and spin configuration for different Jex and D.When Jex=0.0 and the value of D is small,there exist almost same magnetic properties between quantum dots and single cluster.The relation between coercivity and temperature(Hc...