通过范德瓦尔斯铁磁铁Fe4GeTe2进行半金属运输和旋极化道
Anita Halder1,2, Declan Nell1, Antik Sihi1
1School of Physics and CRANN, Trinity College, Dublin 2, Ireland.
Nano letters
|July 22, 2024
概括
在Fe4Ge2中依赖于旋转的运输显示出半金属性质,保持从散装到单层的高旋转极化. 这使得预测的道磁阻比在磁道连接处达到500%.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 这就是Spintronics.
背景情况:
- 范德瓦尔斯 (vdW) 铁磁铁具有独特的电子和磁性特性.
- Fe4Ge2 是一个有前途的 vdW 铁磁铁,用于自旋电子应用.
- 了解自旋依赖运输对于开发下一代电子设备至关重要.
研究的目的:
- 为了研究Fe4Ge2.2的连贯自旋依赖的传输特性.
- 探索电子相关性和自旋轨道合对运输的影响.
- 为了预测Fe4Ge2基磁道连接处的道磁阻力 (TMR).
主要方法:
- 密度函数理论 (DFT) 与不平衡格林函数 (NEGF) 方法相结合.
- 动态平均场理论 (DMFT) 用于量子传输计算.
- 对电子结构和传输特性进行初始计算.
主要成果:
- Fe4Ge2表现出半金属的行为,其导电性几乎有100%的旋转极化,从散装到单层持续存在.
- 在偏差电压下和在旋转轨道合下,旋转极化保持稳健.
- 电子相关性对磁性具有重要意义,但对导电率的影响很小.
- 预计Fe4Ge2/vdW间隙/Fe4Ge2连接处的高TMR比率约为500%.
结论:
- Fe4Ge2是一种高度自旋极化的材料,适合用于自旋电子设备.
- 预测的高TMR比率表明了先进磁性内存和逻辑应用的潜力.
- 通过优化接口结构,可以进一步增强TMR.
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