由拓绝缘体产生的旋转转移扭矩
A R Mellnik1, J S Lee2, A Richardella2
1Cornell University, Ithaca, New York 14853, USA.
Nature
|July 25, 2014
概括
拓绝缘体,如甲化物,通过旋转转移扭矩有效地控制磁性材料. 这一突破可能会导致先进的,低功率的磁性内存和逻辑设备.
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:
- 磁性设备提供非挥发性,高密度,高速,耐用性内存和逻辑解决方案.
- 有效的电流驱动磁化操纵对于磁性技术的广泛采用至关重要.
- 通过旋转霍尔或拉什巴-埃德尔斯坦效应,旋转轨道相互作用是电流驱动扭矩的关键机制.
研究的目的:
- 研究拓绝缘体的潜力,特别是树脂化物 (Bi2Se3) 对高效的旋转轨道诱导扭矩的潜力.
- 通过实验证明电流驱动的旋转转移扭矩从拓绝缘体表面状态到相邻的铁磁层.
- 为了评估Bi2Se3作为用于磁性操纵的旋转轨道扭矩源的效率.
主要方法:
- 薄膜的制造包括一个拓绝缘体 (Bi2Se3) 和一个铁磁体 (常态合金,Ni81Fe19).
- 在室温下进行电传输测量,以检测电流诱导的磁效应.
- 分析每单位充电电流密度的扭矩强度.
主要成果:
- 在Bi2Se3中的电荷电流在相邻的Ni81Fe19膜上产生了强大的旋转转移扭矩.
- 观察到的扭矩方向与拓绝缘体表面状态的预测保持一致.
- 在Bi2Se3中的扭矩效率超过了之前报告的旋转转移扭矩源,即使在带有散装导体的膜中也是如此.
结论:
- 拓绝缘体,如Bi2Se3,是旋转转移扭矩的高效来源.
- 这项研究证明了使用拓绝缘体的可行性,以高效地对磁性材料进行电气操作.
- 这些发现表明,开发下一代低功耗磁性存储器和在室温下运行的逻辑设备是一个有希望的途径.
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