可调节的超导电在电子和孔 doped 伯纳尔双层石墨烯
Chushan Li1,2, Fan Xu1, Bohao Li3
1Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China.
Nature
|June 19, 2024
概括
当接近WSe2层时,超导性会出现在电子和孔合的伯纳尔双层石墨烯 (BBG) 中. 这种受电场影响的可调的超导性揭示了基于石墨烯的电子系统的新物理.
科学领域:
- 凝聚物质物理学
- 材料科学
- 两维电子系统
背景情况:
- 基于石墨烯的系统为超导研究提供可调的平台.
- 在扭曲石墨烯和特定晶体形式 (RTG,BBG) 中观察到的超导性.
- 最近的研究表明,由于WSe2的接近,BBG的超导性增强.
研究的目的:
- 调查电子和孔 doped 伯纳尔双层石墨烯 (BBG) / WSe2 设备的超导性和风味对称性破坏阶段.
- 通过垂直电场探索超导的可调性.
- 了解WSe2层在观察到的超导性中的作用.
主要方法:
- 制造BBG/WSe2异构结构.
- 静电注以实现电子和孔注.
- 应用垂直电场来调节超导.
- 超导过渡温度的测量 (Berezinskii-Kosterlitz-Thouless)
主要成果:
- 在电子和孔合的BBG/WSe2装置中观察超导性.
- 超导的强度可以通过应用垂直电场来调整.
- 最大Berezinskii-Kosterlitz-Thouless过渡温度为210mK (用电子合剂) 和400mK (用孔合剂).
- 当波函数被驱动到WSe2层时,就会出现超导性.
- 孔配超导违反了保利磁性极限 (类似于冰柱),而电子配超导则遵守了它,具有显著的冰柱旋转轨道合.
结论:
- WSe2层对于诱导和增强BBG中的超导性至关重要.
- 电子和孔杂超导体表现出与保利极限和伊辛特征相关的不同行为.
- 这些发现突出了BBG导电带的丰富物理特性以及基于石墨烯的超导体设备的潜力.
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