在Fe(Te,Se) 范德瓦尔斯约瑟夫森连接处出现的具有超导性的铁磁
Gang Qiu1, Hung-Yu Yang2, Lunhui Hu3
1Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA. gqiu@g.ucla.edu.
Nature communications
|October 23, 2023
概括
我们在基于铁的约瑟夫森连接处观察到界面铁磁性和超导性. 这一发现推动了对量子计算应用的拓超导体的研究.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子计算 材料科学 科学 量子计算 材料科学
背景情况:
- 拓超导体对于容错量子计算机至关重要.
- 由于相互竞争的自旋对齐,实现并发的铁磁性和超导性是具有挑战性的.
- 为这些属性寻求一个统一的材料平台.
研究的目的:
- 为了研究铁基超导体的界面铁磁性.
- 探索铁磁和超导状态之间的相关性.
- 为了证明通往拓超导的途径.
主要方法:
- 使用铁基超导体Fe ((Te,Se) 制造范德瓦尔斯约瑟夫森连接点.
- 在设备层面进行传输测量,以检测磁性歇斯底里和超导特性.
- 分析弗劳恩霍弗模式,以确定铁磁的位置.
主要成果:
- 在超导临界温度以下的连接电阻中观察到磁性歇斯底里.
- 通过在弗劳恩霍弗模式中混合0-π相证实了界面铁磁性.
- 检测到一个无静态场超导二极管效应,效率高达10%,证实时间逆向对称性破坏.
结论:
- 在 Fe ((Te,Se) Josephson 连接处证明了并发的铁磁性和超导性.
- 提供了与超导性相关的界面铁磁的证据.
- 开辟了用于量子计算的基于铁的材料的拓超导性的新途径.
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