共掺杂BiFeO3薄膜铁电、铁磁性能及磁电耦合的研究

项目名称： 共掺杂BiFeO3薄膜铁电、铁磁性能及磁电耦合的研究

项目编号： No.11304273

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： 王前进

作者单位： 云南师范大学

项目金额： 26万元

中文摘要： 室温下同时具有铁电性和反铁磁性的BiFeO3多铁材料在传感器、自旋电子学、信息存储等方面有广阔的应用前景，近来备受人们的关注。如何同时提高BiFeO3材料的铁电、铁磁及磁电耦合性能是当前研究的一个难点。本项目紧密结合BiFeO3中A位掺杂、B位掺杂(如A=La，B=Mn)能大大提高体系的铁电性以及SrTiO3和BaTiO3中N掺杂O位能产生磁性的实验进展，抓住BiFeO3薄膜中利用O位掺杂2p轻元素(N、C)来提高体系铁磁及磁电耦合的新思路，用第一性原理计算方法探索La和N(C)共掺杂、Mn和 N(C)共掺杂、及本征缺陷和掺杂浓度对BiFeO3薄膜铁电、铁磁及磁电耦合性能的影响。通过对体系的几何构型，电子结构及成键机制的分析，获得微观物理模型和物理图像，为同时提高BiFeO3材料的铁电、铁磁及磁电耦合性能提供理论分析基础和实验指导。

中文关键词： 多铁性；掺杂；铁磁性；自发极化；

英文摘要： Multiferroic materials have broad applications in sensor, spintronics, information storage and the like. BiFeO3, which simultaneously exhibits ferroelectricity and antiferromagnetic ordering at room temperature, has been widely studied in recent years. One difficult point of current research is how to simultaneously improve the ferroelectricity, ferromagnetism and magnetoelectric coupling in BiFeO3. The subject closely combines with the experimental progress that ferroelectricity can be improved by using A-site and B-site doping (such as A=La, B=Mn) in BiFeO3 and magnetism can be produced by using N doping in SrTiO3 and BaTiO3, grasping the new idea that ferromagnetism and magnetoelectric coupling are improved by using 2p light elements (N, C) doping at O-site in BiFeO3 film, using first-principles to explore the influence of La and N(C) codoping, Mn and N(C) codoping, native defects and doping concentration on the ferroelectricity, ferromagnetism and magnetoelectric coupling in codoping BiFeO3 films. Through analyzing on the geometric configuration, electronic structure and bonding mechanism of the system, getting the microscopic physical model and physical pictures, which can supply theoretical analysis basis and experimental guide for simultaneously improving the ferroelectricity, ferromagnetism and magnetoel

英文关键词： multiferroic properties；doping；ferromagnetism；spontaneous polarization；