纳米晶多铁性材料中子衍射研究

项目名称： 纳米晶多铁性材料中子衍射研究

项目编号： No.11475268

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 武梅梅

作者单位： 中国原子能科学研究院

项目金额： 92万元

中文摘要： 多铁材料是指同时具备两种或两种以上初级铁性体（铁电性、磁性和铁弹性）特征的材料，在信息储存、自旋电子器件、磁传感器等领域具有广阔的应用前景。中子衍射技术可以准确测定轻元素的原子位置以及微观磁结构信息，已成为研究多铁材料不可或缺的重要技术手段。本项目拟以BiFeO3多铁性材料为研究对象，通过改变Bi和Fe位化学组分，制备系列不同尺寸的纳米晶粉体，从微观结构上调制其螺旋磁性和铁电性。结合中子及X射线粉末衍射等研究手段，系统研究材料微观结构（晶体结构和磁结构）与基本电磁性随晶粒尺寸、化学成分、温度、磁场和压力的演化规律，拓展多铁材料微观结构与物性之间关系的认识，揭示磁电耦合的产生机制，促进多铁材料的发展。

中文关键词： 中子衍射；纳米晶；多铁性材料；磁结构；磁电耦合

英文摘要： Multiferroic materials, in which more than one primary ferroic order parameters (ferromagnetism, ferroelectricity, ferroelasticity) coexist, which have received much attention due to their potential applications in information storage, spintronic devices and magnetic sensor et al. Neutron diffraction can precisely determine the atom positions of light elements and magnetic structure, which has become the most important technique for multiferroic material research. The goal of this project is to optimize the multiferroic properties of BiFeO3 by changing the composition at Bi and Fe sites and the size of nanocrystalline powders. Combining X-ray and neutron powder diffraction, the variation of microscopic structures and electric-magnetic properties with nanocrystallize size, chemical element, temperature, pressure, magnetic field will be investigated. The targets of this project are (i) to provide new ideas for the relationship between microscopic structures and multiferroic properties; (ii) to elucidate the mechanism of the magnetoelectric coupling. This research will have great significance for the development of multiferroic materials.

英文关键词： neutron diffraction;nanocrystalline;multiferroic materials;magnetic structure;magnetoelectric coupling