项目名称: Hg2CuTi型全Heusler合金表面与界面的半金属特性研究
项目编号: No.11264041
项目类型: 地区科学基金项目
立项/批准年度: 2013
项目学科: 数理科学和化学
项目作者: 金迎九
作者单位: 延边大学
项目金额: 50万元
中文摘要: 半金属材料具有特殊的能带结构,即一种自旋取向的电子态具有金属性,而另一种自旋取向的电子态呈现半导体特性,因此在费米能级处具有100%自旋极化率;这种特性在自旋电子学领域具有非常重要的应用价值。最近的实验和理论研究表明,Hg2CuTi型全Heusler合金涵盖着大量的半金属材料。本项目采用全势线性缀加平面波(FLAPW)方法,着重研究Hg2CuTi型全Heusler合金Mn2YZ、Cr2YZ、Ti2YZ(Y为过渡金属元素,Z为sp元素)的电子结构、磁性与半金属特性,并进一步研究具有半金属特性的Mn2、Cr2和Ti2基全Heusler合金的(001)表面以及此表面与闪锌矿结构半导体(001)表面所形成的异质结界面的半金属特性,从而将探索具有较大能隙、高居里温度和结构稳定性好的半金属材料。上述研究为半金属材料的实际应用提供重要的理论依据。
中文关键词: 半金属特性;Heusler 合金;自旋极化率;电子结构;第一性原理计算
英文摘要: Half-metallic materials have a unique property in their band structure: one of the spin bands is metallic, while the other is semiconducting, which brings 100% spin polarization at the Fermi level. The materials have potential applications in spintronics. Recent experimental and theoretical researchs reveal that the full-Heusler alloys with an Hg2CuTi-type structure can belong to the family of half-metallic materials. We investigate the electronic structures, magnetism, and half-metallicity of full-Heusler Mn2YZ, Cr2YZ, Ti2YZ (Y denotes some transition metal element, Z is an sp element) alloys with an Hg2CuTi-type structure by using the full-potential linearized augmented plane wave (FLAPW) method. In addition, we study the half-metallicity for the (001) surfaces of Mn2, Cr2, Ti2 based half-metallic full-Heusler alloys and the (001) interfaces between the half-metallic full-Heusler alloys and the zinc-blende semiconductors. The research will be exploring the half-metallic materials with a large band-gap, high Curie temperature, and good structural stability, which can provide theoretical evidence for practical application of the half-metallic materials.
英文关键词: half-metallicity;Heusler alloy;spin-polarization;electronic structures;first-principles calculation