New Heusler compounds with large perpendicular magnetic anisotropy and for spin-torque application

该项目的目标是设计用于自旋扭矩应用的新型四方半金属化合物。Heusler化合物可设计为低阻尼材料，其阻尼值小于传统铁磁性金属，如CoFe。众所周知，Co2YZ Heusler化合物是理论上唯一在隧道结中实现高自旋极化的半金属化合物。在高居里温度下，CoMn2Z等亚铁磁性Heusler化合物和Mn3Ga等相关化合物的饱和磁化强度降低。然而，四方Heusler化合物由于其巨大的垂直磁各向异性而引起了人们的特别兴趣。尤其是含镓、锡的Heusler化合物表现出结构不稳定性。在该项目中，将合成和研究几种可能的四方形变铁磁和亚铁磁性候选材料，如Mn2FeZ、CoMn2Z、XCr2Z和XMn2Z。

Goal of this project is the design of new tetragonal half-metallic compounds for spin torque application. Heusler compounds can be designed as low-damping materials, with damping values smaller than for conventional ferromagnetic metals such as CoFe. It is well established that the Co2YZ Heusler compounds are the only theoretical half metallic compounds for which high spin polarisation was realized in tunnel junctions. A reduced saturation magnetization despite a high Curie temperature can be found for ferrimagnetic Heusler compounds such as CoMn2Z and related compounds such as Mn3Ga. However, tetragonal Heusler compounds are of special interest due to their large perpendicular magnetic anisotropy. Especially Heusler compounds with Gallium and Tin show the structural instabilities. Several possible ferro- and ferrimagnetic candidates with tetragonal distortion will be synthesized and investigated within the project such as Mn2FeZ, CoMn2Z, XCr2Z, and XMn2Z.