在La(Mn,Zn) AsO合金中通过元素替代进行室温半金属性
Xingxing Li1, Xiaojun Wu, Jinlong Yang
1Hefei National Laboratory for Physical Science at the Microscale, ‡CAS Key Laboratory of Materials for Energy Conversion and Department of Materials Science and Engineering, and §Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.
Journal of the American Chemical Society
|March 29, 2014
概括
研究人员设计了一种新的半金属材料用于自旋电子设备. 在La(Mn0.5Zn0.5) AsO中的元素替代产生了广泛的半金属间隙和高的基里温度,提高了旋转电子设备的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 开发高性能自旋电子设备需要具有特定性质的材料,如高基里温度,宽半金属间隙和大磁性异构.
- 目前的材料往往不能达到这些理想的特性,需要探索新的化合物.
研究的目的:
- 设计一个实用的半金属材料,具有可取的特性,用于自旋电子应用.
- 为了研究元素替代对层层的La(Mn0.5Zn0.5) AsO.电子和磁性质的影响.
主要方法:
- 用第一原则计算来设计和分析材料.
- 在La(Mn0.5Zn0.5) AsO合金中系统地引入了元素替代物 (兴奋剂).
- 基于伊辛模型的蒙特卡洛模拟被用来预测基里温度.
主要成果:
- 原始的La(Mn0.5Zn0.5) AsO合金是一种反铁磁半导体.
- 孔或电子兴奋剂诱导了半金属性,具有0.74 eV的显著半金属间隙.
- 预测的基里温度达到475K (25%的Ca doping) 和600K (50%的H doping).
- 合金表现出很大的磁性异构能量,超过了散装Fe,Co和Ni的能量.
结论:
- 以元素替代的La(Mn0.5Zn0.5) AsO是高性能自旋电子器件的有希望的候选者.
- 设计的材料表现出广泛的半金属间隙,高基里温度和大磁性异性质的有利组合.
- 这项工作为开发先进的自旋电子材料提供了可行的途径.
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