没有平衡 分数约瑟夫森效应
Aritra Lahiri1, Sang-Jun Choi1, Björn Trauzettel1,2
1Institute for Theoretical Physics and Astrophysics, University of Würzburg, D-97074 Würzburg, Germany.
Physical review letters
|October 6, 2023
概括
电压脉冲在超导连接处诱导了一种新的分数约瑟夫森效应. 这种由准粒子干扰驱动的不平衡现象,甚至在具有Majorana束状态的拓交点中也能观察到.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 超导电性 超导电性 超导电性
- 量子电子学 量子电子学
背景情况:
- 约瑟夫森道交叉点通常显示超级电流与sin (φ) 相称.
- 此外,A cos (φ) 项和电子减速效应也存在.
- 没有平衡条件可以改变交叉点的行为.
研究的目的:
- 调查时间变化的电压脉冲对约瑟夫森连接点的影响.
- 分析非平衡分数约瑟夫森效应 (NFJE) 的出现.
- 检查NFJE在拓上的约瑟夫森连接点与Majorana的边界状态.
主要方法:
- 在脉冲电压下对约瑟夫森道交叉点进行显微镜分析.
- 理论上研究了sin (φ) 和cos (φ) 项之间的相互作用.
- 研究接近零频和准粒子激发的束状态.
主要成果:
- 时间变化的电压脉冲显著增强了cos (φ) 项.
- 一个不平衡的分数约瑟夫森效应 (NFJE) 与sin (φ/2) 相称.
- NFJE是由非平衡虚拟准粒子激发的干扰引起的.
- 在拓上的约瑟夫森结点中,NFJE独立于基态费米子平价.
结论:
- 脉冲电压将约瑟夫森连接点驱动到一个新的不平衡状态.
- NFJE为探索超导体中的量子现象提供了一个新的途径.
- 拓约瑟夫森交点表现出独特的NFJE属性,与平衡行为不同.
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