通过反铁磁绝缘体通过磁介导旋转扭矩进行磁化切换
Yi Wang1,2, Dapeng Zhu1, Yumeng Yang1
1Department of Electrical and Computer Engineering, National University of Singapore, 117576, Singapore.
概括
研究人员使用磁电流演示了高能效的磁化切换,为旋转器件提供了基于电子的旋转转矩的有希望的替代方案.
科学领域:
- 机器人
- 凝聚物质物理学
- 材料科学
背景情况:
- 对于磁性设备来说,有效地操纵局部磁化是至关重要的.
- 电旋转转矩 (STT) 是一种常见的方法,但由于朱尔加热而导致高能耗.
- 开发用于磁化控制的节能替代品是一个活跃的研究领域.
研究的目的:
- 通过实验证明使用磁流进行磁化切换的替代方法.
- 在室温下研究磁性转换的可行性.
- 评估马格农电流在转移旋转角动量的效率.
主要方法:
- 制造Bi2Se3/抗铁磁绝缘体NiO/铁磁异构结构.
- 使用马格农电流诱导旋转转移.
- 通过磁扭矩进行磁化切换的实验演示.
主要成果:
- 在室温下在Bi2Se3/NiO/铁磁器件中实现磁性转换.
- 马格农电流有效地通过25纳米的NiO层传递旋转角动量,而无需电子参与.
- 马格农扭矩效率与之前报告的电转扭矩比率相当.
结论:
- 马格农电流提供了一种节能控制磁化的机制,克服了电 STT 的局限性.
- 这项研究为开发先进的,低分散的旋转记忆和逻辑设备铺平了道路.
- 这些发现为基于磁的自旋电子和设备应用领域带来了活力.
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