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在CoFe/CuO轨道扭矩系统中减轻吉尔伯特阻尼
Shilei Ding1, Hanchen Wang1, William Legrand1
1Department of Materials, ETH Zürich, 8093 Zürich, Switzerland.
Nano letters
|August 12, 2024
概括
部分氧化3d金属产生强大的轨道扭矩与低磁阻尼,与5d金属不同. 这一发现为高效的旋转轨道扭矩应用提供了新的途径,而无需增加阻尼.
科学领域:
- 这就是Spintronics.
- 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
背景情况:
- 旋转轨道扭矩对于在磁性/非磁性双层中产生旋转电流至关重要.
- 像5d金属这样的高效的自旋电流源往往会充当自旋沉没器,增加磁性阻尼.
研究的目的:
- 为了研究一个部分氧化3d金属作为轨道扭矩的来源与最小的阻尼.
- 为了比较CoFe/CuOx和CoFe/Pt系统中的扭矩效率和阻尼.
主要方法:
- CoFe/CuOx和CoFe/Pt双层的制造和表征.
- 测量扭矩效率 (ξ) 和吉尔伯特阻尼 (α).
主要成果:
- 与CoFe/Pt (Δα ≈ 0.005-0.02) 相比,CoFe/CuOx表现出强大的轨道扭矩,阻尼增加明显较低 (Δα < 0.002).
- 在这两种系统中,扭矩效率 (ξ) 是可比的.
- 观察到的CoFe/CuOx的非互惠关系归因于轨道旋转电流比较低和缺乏有效的旋转沉降.
结论:
- 部分氧化3d金属提供了一种有效的途径,可以在没有大量磁阻尼的情况下产生轨道扭矩.
- 这一发现为开发具有高效磁化动态的先进自旋电子设备提供了新的见解.
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