非局部运输的边缘依赖在间隙双层石墨烯中
Hyeon-Woo Jeong1, Seong Jang1, Sein Park1
1Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
Nano letters
|December 9, 2024
概括
边刻双层石墨烯 (BLG) 创造了导电通道,改变了电子传输. 这挑战了先前关于间隙BLG的拓性质的说法,表明边缘效应对观察到的电阻变化负责.
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
- 纳米技术纳米技术
背景情况:
- 间隙石墨烯的拓性质被研究为valleytronics.
- 之前的实验显示了大非局部阻力在Hall-bar设备,表明拓行为.
- 两个层间隙石墨烯 (BLG) 中这种抗性的起源仍然不清楚.
研究的目的:
- 为了研究边缘蚀刻对双门双层石墨烯 (BLG) 装置中的电子传输的影响.
- 为了澄清间隙BLG中非局部电阻的起源.
- 为了确定观察到的运输现象是由于拓性质或边缘效应.
主要方法:
- 制造双门双层石墨烯 (BLG) 设备,其边缘具有自然裂痕.
- 使用氧气等离子体工艺进行边蚀刻前后电子传输的表征.
- 测量局部和非局部电阻作为移位场的函数.
主要成果:
- 在蚀刻之前,局部电阻随着位移场的指数增长,非局部电阻与欧姆贡献相匹配.
- 蚀刻后,局部电阻与增加的位移场和.
- 蚀刻后的非局部电阻与欧姆贡献有显著的偏差 (2 个数量级).
结论:
- 观察到的局部和非局部电阻的变化归因于等离子蚀刻后边缘导电通道的形成.
- 这些发现表明,边缘效应,而不是内在的拓性质,解释了间隙BLG中变化的电子传输.
- 这项工作为解释在间隙石墨烯系统中的运输实验提供了新的视角.
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