相关绝缘体和切尔恩绝缘体在五层方圆体堆叠的石墨烯中
Tonghang Han1, Zhengguang Lu1, Giovanni Scuri2,3
1Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature nanotechnology
|October 5, 2023
概括
五层形石墨烯表现出独特的相关绝缘和拓状态,由平面带和电场驱动. 这种自然材料系统提供了对电子相关性和拓学的见解,而不需要复杂的工程.
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
- 量子现象是一种量子现象.
背景情况:
- 多层石墨烯具有接近零能量的平面带,这表明可能存在相关的电子现象.
- 电子相关性可以打破等旋对称性,可能导致受贝里相影响的拓学上非微不足道的状态.
研究的目的:
- 在低温下研究六边形化封装五层石墨烯中的电子运输.
- 探索相关的电子现象和可通过该材料中的电场调节的拓状态.
主要方法:
- 低温 (100 mK) 电力传输测量. 低温 (100 mK) 电力传输测量.
- 电位移场 (D) 和磁场的应用.
- 与紧密结合计算进行比较.
主要成果:
- 在零电荷密度和位移场时观察到相关的绝缘状态,与理论金属预测相反.
- 确定了一个切尔恩绝缘体状态 (C=-5) 和其他拓状态 (C=-3),其移位场的增加.
- 在高电场和电荷密度下发现异回旋极化四分之一和半金属.
结论:
- 五层形石墨烯表现出两个明显的费米表面不稳定性,一个来自平面带,另一个来自斯通纳机制.
- 这种材料作为一个平台,用于研究电子相关性和拓在内在石墨系统的相互作用.
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