项目名称: 铁磁/反铁磁超晶格自组装体系的构建与磁学性质研究
项目编号: No.21301040
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 数理科学和化学
项目作者: 李建军
作者单位: 哈尔滨工业大学
项目金额: 25万元
中文摘要: 铁磁/反铁磁耦合体系的'交换偏置效应',已经在巨磁电阻效应的磁电子器件中得到广泛应用并开启了自旋电子学的发展。但由于技术所限,难以对铁磁与反铁磁耦合薄膜及核-壳体系中界面交换作用的本质进行深入的研究。故本研究以铁、锰的油酸化合物为前驱体,在1-十八烷烯等介质中通过热分解方法制备亚铁磁四氧化三铁(Fe3O4)以及反铁磁氧化锰(MnO)纳米颗粒;控制纳米颗粒的形貌以及纳米颗粒的粒径尺寸,用制备的四氧化三铁以及氧化锰纳米颗粒作为基本基元实现二元铁磁/反铁磁超晶格体系的构建;研究不同结构超晶格体系的磁学性能,分析铁磁/反铁磁超晶格体系界面相互作用与磁学性能(主要是交换偏置场)的内在关联机理。以磁性纳米颗粒为构建基元的铁磁/反铁磁超晶格体系具有清晰明了的界面交换作用,可有效深入探索界面相互作用与交换偏置场之间的关系,进而为进一步揭示'交换偏置效应'的物理机理提供实验依据。
中文关键词: 溶胶-凝胶;磁致伸缩;静电纺丝;二氧化硅纤维;
英文摘要: Exchange-bias (a shift in the soft magnetization curve) is the most famous effect resulting from the coupled ferromagnetic/antiferromagnetic systems. The phenomenology of exchange bias has been extensively investigated. The essential physics underlying the phenomenon are the dynamics of domain walls in antiferromagnet and the exchange interaction between the antiferromagnet and ferromagnet at their interface. For technical reason, it is difficult to determine the magnetic configuration at the interface. Superlattices self-assembled from monodisperse nanocrystals are attracting great attention because of their potential applications in electronic, optoelectronic, and magnetic devices. In order to investigate the nature of interfacial exchange interaction in the exchange bias systems, we fabricate binary magnetic nanocrystal superlattices (periodically ordered arrays of magnetic nanocrystals with two different well-defined diameters). Compared with the coupled bilayer and core-shell ferromagnetic/antiferromanetic systems, binary ferromagnetic/antiferromanetic superlattices self-assembled from magnetic nanocrystals have clear magnetic interfacial interactions. Here, Fe3O4 and MnO monodisperse nanocrystals will be prepared by the thermal decomposition of metal-oleate complex in high boiling solvents. Particle si
英文关键词: sol-gel;magnetostrictive;electrospinnning;silica fiber;