轨道切尔恩绝缘体中的电磁顺序切换
H Polshyn1, J Zhu2, M A Kumar1
1Department of Physics, University of California, Santa Barbara, Santa Barbara, CA, USA.
Nature
|November 24, 2020
概括
研究人员使用石墨烯异构结构在轨道切尔恩绝缘体中展示了磁场的直接电场控制. 这一突破使不可挥发的磁切换成为可能,为先进的自旋电子和低功耗内存设备铺平了道路.
科学领域:
- 凝聚物质物理学
- 材料科学
- 量子现象
背景情况:
- 磁力通常依赖于电子旋转,使电场控制具有挑战性.
- 轨道切尔恩绝缘体提供了由于拓性质的新型磁态的潜力.
- 现有的电磁控制方法间接且技术有限.
研究的目的:
- 通过实验证明磁场的直接电场控制.
- 在工程异构结构中研究轨道切尔恩绝缘体的特性.
- 探索旋转电子和磁性存储器的潜在应用.
主要方法:
- 使用石墨烯制造范德瓦尔斯异构结构.
- 使用旋转缺陷的石墨烯单层和双层系统来创建moiré小频段.
- 在特定的电子填充中测量量子化异常霍尔效应 (QAHE).
- 使用场效应控制来操纵化学潜力并诱导磁态逆转.
主要成果:
- 量子化异常霍尔效应 (QAHE) 的观测,横向电阻为~h/2e2.
- 演示自发的极化成一个单谷投射带与切尔恩号码二.
- 通过电场控制实现了磁性状态的非挥发性,歇斯底里反转.
- 对拓边缘状态的实验证据驱动磁状态逆转.
结论:
- 在轨道切尔恩绝缘体中对磁场的直接电场控制在实验上是可行的.
- 工程化石墨烯异构结构为实现这些现象提供了一个平台.
- 观察到的效应对开发下一代电子设备,包括可重新配置电路和超低功率磁记忆具有重要意义.
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