CoO包覆的Co纳米颗粒的磁滞回线的横向及纵向偏移

稀有金属, 2006, 30(3): 263-265. doi: 10.3969/j.issn.0258-7076.2006.03.001

CoO包覆的Co纳米颗粒的磁滞回线的横向及纵向偏移

温戈辉 ^1, , 郑荣坤 ^2, , 冯国光 ^3, , 张西祥 ^4,

1.吉林大学超硬材料国家重点实验室,吉林,长春,130012

2.香港科技大学物理系,香港,999077

3.香港科技大学物理系,香港,999077

4.香港科技大学物理系,香港,999077

基金项目: 中国科学院资助项目(50402003) 香港研究资助局资助项目(HKUST6140/00P)

关键词：纳米颗粒 , 交换偏置 , 核-壳结构 , 钴

Horizontal and Vertical Shifts of Hysteresis Loop in CoO Coated Co Nanoparticles

利用等离子体-气体冷凝方法制备了具有核-壳结构的Co纳米颗粒,并对其结构和磁性进行了研究.结果表明纳米颗粒的尺寸均匀,平均直径约为20 nm,表面包覆着CoO壳层.在CoO壳层和Co核间存在着交换偏置效应.经过磁场冷却,在低温测量的纳米颗粒的磁滞回线不只在横轴方向,在纵轴方向也存在着明显的偏移,并且在横向偏移量和纵向偏移量间存在着线性关系.交换偏置效应和磁滞回线的纵向偏移应该起源于CoO壳层中未被补偿的冻结自旋.根据交换偏置效应的未补偿自旋模型,对Co纳米颗粒的磁场冷却磁滞回线的横向偏移量和纵向偏移量间的线性关系进行了解释.

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材料期刊网

CoO包覆的Co纳米颗粒的磁滞回线的横向及纵向偏移

Horizontal and Vertical Shifts of Hysteresis Loop in CoO Coated Co Nanoparticles

参考文献