在基于海斯勒合金的旋转无间隙半导体薄膜中产生大热旋转效应
Amit Chanda1, Deepika Rani2, Derick DeTellem1
1Department of Physics, University of South Florida, Tampa, Florida 33620, United States.
ACS applied materials & interfaces
|November 8, 2023
概括
与散装材料相比,Heusler合金CoFeCrGa薄膜具有显著增强的异常Nernst系数 (ANE) 和纵向旋转Seebeck效应 (LSSE). 这些发现为先进的自旋电子设备铺平了道路.
科学领域:
- 这就是Spintronics.
- 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
背景情况:
- 由于其高基里温度和自旋极化,海斯勒合金对自旋电子应用具有前景.
- 旋转无间隙半导体 (SGS) 为先进的电子设备提供可调节的特性.
研究的目的:
- 在CoFeCrGa薄膜中研究温度依赖的异常Nernst效应 (ANE) 和纵向旋转Seebeck效应 (LSSE).
- 将这些薄膜的性能与散装材料和其他磁性系统进行比较.
- 了解在这些异构结构中控制ANE和LSSE的基本机制.
主要方法:
- 在MgO基板上制造CoFeCrGa薄膜.
- 在一系列温度范围内测量ANE和LSSE系数.
- 利用无线电频率横向灵敏度和宽带铁磁共振.
- 相关联的LSSE信号与磁性异构和吉尔伯特缩.
主要成果:
- 在MgO/CoFeCrGa (95nm) 薄膜上显示了在室温下≈1.86μV K-1的ANE,大大超过了散装CoFeCrGa.
- 对于MgO/CoFeCrGa (95 nm) /Pt (5 nm) 异构的LSSE系数是≈20.5 nV K-1 Ω-1,是La0.7Sr0.3MnO3.3的两倍.
- 无论是ANE还是LSSE都显示出相同的温度依赖性,由于磁散射和群体效应,温度依赖性达到225K.
- 外在的偏斜散射被确定为ANE的主导机制.
结论:
- 与散装材料和一些已知材料相比,CoFeCrGa薄膜显示出优越的ANE和LSSE性能.
- ANE和LSSE的温度依赖与马格农动力学有关.
- 建立了LSSE,磁性异构和吉尔伯特阻尼之间的相关性.
- 这些发现对于开发高效的基于海斯勒合金的自旋热量纳米器件至关重要.
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