在二维的GeC/CrN异构体中强大的铁磁性
Y Ozguven1, H E Guler2, A A Billur3
1Department of Metallurgical and Materials Engineering, Sivas Cumhuriyet University, 58140, Sivas, Turkey.
Physical chemistry chemical physics : PCCP
|August 15, 2023
概括
碳化物 (GeC) 和化 (CrN) 异构体表现出半金属性和高基里温度,这使得它们对螺旋电子学具有前景. 应变工程进一步调整它们的磁性特性,以满足潜在的应用.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 这就是Spintronics.
背景情况:
- 探索用于先进电子和磁性应用的新二维材料.
- 异构体通过材料组合和堆叠提供可调节的特性.
- 碳化 (GeC) 和化 (CrN) 是旋转器件的有希望的候选物.
研究的目的:
- 研究GeC/CrN异构体的电子和磁性特性.
- 确定堆叠,扭转角度和双轴应变对材料性能的影响.
- 评估GeC/CrN异构体在自旋电子应用中的潜力.
主要方法:
- 使用密度函数理论 (DFT) 的第一原则计算与哈伯德U校正.
- 有效的无极形海森堡自旋模型用于磁性属性.
- 对动态稳定性的Phonon光谱分析.
- 对于基里温度计算的随机相近似法 (RPA).
主要成果:
- 所有堆叠配置都表现出半金属性和外平面铁磁基态.
- 对于GeC/CrN异构体,预测了高基里温度 (Tc).
- 半金属性是独立于堆叠和扭曲角度的.
- 双轴应变显著影响磁性异构能量和基里温度,其值保持在室温以上.
结论:
- GeC/CrN异构体具有动态稳定性,并具有可取的半金属铁磁性质.
- 应变工程提供了一条调整磁性异构和库里温度的途径.
- 宽带间隙,相应格子和高Tc的组合使 CrN 在 GeC 上成为未来自旋电子设备的强有力的候选人.
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