在弹道双流体中依赖费尔米速度的临界电流 石墨烯 约瑟夫森交叉点
Amis Sharma1, Chun-Chia Chen2, Jordan McCourt2
1Department of Physics and Astronomy, Texas A&M University, College Station, Texas 77843, United States.
ACS nanoscience Au
|April 21, 2025
概括
我们研究了双层石墨烯约瑟夫森结点,发现它们的临界电流依赖于温度. 这种依赖性允许调整费米速度和载体密度,与单层石墨烯设备不同.
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
- 量子电子学 量子电子学
背景情况:
- 比莱尔石墨烯约瑟夫森结 (BGJJs) 对电子设备来说是有前途的.
- 了解它们的运输特性对于高级应用至关重要.
研究的目的:
- 研究BGJJs的温度和载体密度的依赖性.
- 确定双层石墨烯中的费米速度.
- 将BGJJ与单层石墨烯Josephson连接进行比较.
主要方法:
- 在近距离的弹道BGJJ上进行运输测量.
- 差电阻测量作为偏移电流和门电压的函数.
- 对临界电流 (Ic) 温度依赖性的分析.
主要成果:
- 临界电流遵循一个指数式温度趋势: exp(-kB*T/δE).
- 提取的费米速度随着门电压的增加而增加.
- δE显示了由于双层石墨烯的二次分散而导致的载体密度依赖.
结论:
- 双叶石墨烯约瑟夫森连接提供可调的费米速度和载体密度.
- 这与单层石墨烯形成鲜明对比,为设备提供了新的控制参数.
- 这些发现推动了基于石墨烯的超导电子的发展.
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