Preparation of Transparent Oxides With Ferromagnetic and Ferroelectric Properties at room temperature by Doping Mn and La

掺杂Mn、La制备室温铁磁、铁电透明氧化物

基本信息

批准号：
14550295
负责人：
GOMI Manabu
金额：
$ 2.3万
依托单位：
Nagoya Institute of Technology (2003)Japan Advanced Institute of Science and Technology (2002)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

In this research, we have investigated the mechanism of ferromagnetic behavior exhibiting high Curie temperatures observed for perovskite-type dielectric oxides ABO_3(A=Sr, Ba, Ca, Pb, B=Ti, Zr) doped with La-Mn. In addition, we discussed the possibility of electric field-controlled magnetism through the investigation of relationship between the ferromagnetic and dielectric properties. The obtained results are as follows;1. La-Mn doped ATiO_3 (A=Sr, Ba, Ca) ceramics are ferromagnetic at room temperature, exhibiting magnetizations proportional to the Mn amount. The magnitude of observed magnetization depends on the final sintering temperature, reduced rapidly above 1200℃ at which the sintering density becomes higher.2. The high-resolution TEM observation and EDX composition analysis showed that there is a Mn-rich crystalline region around the grain boundaries for some La-Mn : BaTiO_3 ceramics. In addition, small peaks indicative of the ferromagnetic phase (La, Ba) MnO_3 were detected for these ceramics with the doped amount of La and Mn increasing.These result indicated that the ferromagnetism observed at room temperature is possibly ascribed to precipitation of a small amount of ferromagnetic manganite into the dielectric matrix.3. The 1 mol. % La-Mn doped BaTio_3 ceramics exhibiting simultaneously large magnetization and ferroelectricity at room temperature have been successfully prepared for the first time.It was found that the spontaneous magnetization of 1 mol. % La-Mn doped BaTio_3 ceramics exhibits the reduction as large as 45% for the applied electric field of 1.3 KV/mm. This reduction of magnetization by the electric field is of achieved for the first time and open the door to the control of magnetic moment using electric field.

在这项研究中，我们研究了表现出对钙钛矿型饮食氧化物Abo_3（a = Sr，ba，ca，ca，pb，b = ti，Zr）的铁磁行为的机制。此外，我们通过投资铁磁和饮食特性之间的关系来讨论电场控制磁性的可能性。获得的结果如下; 1。 La-mn掺杂的ATIO_3（A = SR，BA，CA）陶瓷在室温下是铁磁，表现出与MN量成正比的磁化。观察到的磁化的大小取决于最终的烧结温度，在烧结密度变得更高的情况下迅速降低了1200℃。高分辨率TEM观测和EDX组成分析表明，某些LA-MN的晶界周围有一个富含Mn的晶体区域：Batio_3陶瓷。此外，对于这些陶瓷，检测到铁磁相（LA，BA）MNO_3的小峰，其中LA和MN的掺杂量增加了。这些结果表明，在室温下同时归因于少量的Ferromagagnos Mangomagnos Mannod Mangartrric to dioelectric.dieelectrix。 1摩尔。％la-mn掺杂的batio_3陶瓷在室温下同时表现出大型磁化和铁电性，首次成功制备了。％la-mn掺杂的batio_3陶瓷陶瓷的降低量为1.3 kV/mm的高达45％。电场对磁化的减少首次实现，并为使用电场控制磁矩的门打开了大门。