在磁拓绝缘体中的3D量子异常霍尔效应 百纳米厚的三层层
Yi-Fan Zhao1, Ruoxi Zhang1, Zi-Ting Sun2
1Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA.
Advanced materials (Deerfield Beach, Fla.)
|December 20, 2023
概括
研究人员合成了表现出量子异常霍尔 (QAH) 效应的厚磁拓绝缘体. 这一突破使得探索轴心物理和先进的自旋电子设备成为可能.
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:
- 磁性拓状态具有由磁性旋转配置控制的非微不足道的拓性质.
- 量子异常霍尔 (QAH) 状态,一个零磁场量子霍尔效应,是一个关键的例子.
- 现有的研究主要集中在厚度低于10nm的QAH绝缘体上.
研究的目的:
- 合成和研究具有显著增加厚度 (高达≈106 nm) 的磁性拓绝缘体三层.
- 为了证明三维 (3D) 量子异常霍尔效应在这些更厚的材料中的实现和强度.
- 探索这些厚厚的QAH绝缘体在基础物理和设备应用中的潜力.
主要方法:
- 利用分子束表 (MBE) 来生长磁拓绝缘体三层.
- 系统地改变了磁剂,门电压,温度和外部磁场.
- 测量霍尔电阻和纵向电阻以表征拓状态.
主要成果:
- 成功合成了高达≈106纳米厚的磁性TI三层.
- 在零磁场下观察到量化好的霍尔电阻和消失的纵向电阻,证实了3D QAH效应.
- 在各种实验条件下证明了3D QAH效应的稳定性.
结论:
- 在厚样本中观察到的3D QAH效应表明存在间隙的非脏侧面状态,这些状态不会阻碍量子化.
- 百纳米厚的3D QAH绝缘体为基础物理研究 (例如,轴体物理,磁断) 提供了一个可行的平台.
- 这些材料有望在超越摩尔定律限制的情况下推进电子和自旋电子设备.
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