量子点磁化动力学行为的研究Study of Magnetic Dynamic Properties for Quantum Dots
叶晴莹;钟克华;陈小雅;陈水源;黄志高;
摘要(Abstract):
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.
关键词(KeyWords): 量子点;Monte-Carlo方法;交换耦合;偶极相互作用;磁特性
基金项目(Foundation): 福建省自然科学基金重点资助项目(E0320002)
作者(Authors): 叶晴莹;钟克华;陈小雅;陈水源;黄志高;
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