在高电场的双层石墨烯中,内零能量的兰道平面交叉点
Feixiang Xiang1,2, Abhay Gupta1,2, Andrey Chaves3,4
1School of Physics, University of New South Wales, Sydney, New South Wales 2052, Australia.
Nano letters
|October 26, 2023
概括
我们使用磁传输测量在双层石墨烯中探索了尚未探索的零能量兰道水平 (zLL). 在高电场上观察到新的兰道水平交叉,与低电场相比,揭示了不同的量子状态和行为.
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
- 量子力学就是量子力学.
背景情况:
- 比莱尔石墨烯的可调节带结构,特别是零能量兰道水平 (zLL),为新的量子状态提供了潜力.
- 在高电场下zLL的行为在很大程度上仍然没有特征.
研究的目的:
- 在高电场下的双层石墨烯中研究零能量兰道水平的尚未探索的特性.
- 描述量子霍尔态及其在高电场中的过渡.
主要方法:
- 在双层石墨烯样本上进行了磁传输测量.
- 应用了高横电场来探测电子属性.
主要成果:
- 在高电场下,在填充因子 ν = -2,1 和 3 处检测到以前未被观察到的兰道水平交叉点.
- 在高电场下的量子霍尔态的轨道,谷和自旋特征与在低电场下的不同.
- 确定了在 ν = -2 的状态之间的新型,门偏差控制的过渡,轨道和自旋两极分化的变化.
- 在 ν = 0 → 1 和 ν = 2 → 3 之间观察到异常过渡.
结论:
- 观察到的兰道级别交叉路口为零能量兰道级别的理论模型提供了关键的约束.
- 高电场极大地改变了双层石墨烯中量子霍尔态的性质.
- 这些发现突出了对双层石墨烯量子状态的电场控制的潜力.
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