在Bi2SE3/NbSe2的Josephson连接处,异常的电流相位关系和约瑟逊二极管效应的非Majorana起源
Andrei Kudriashov1,2, Xiangyu Zhou1,2, Razmik A Hovhannisyan3
1Department of Materials Science and Engineering, National University of Singapore, Singapore, Singapore.
Science advances
|June 13, 2025
概括
研究人员开发了一种新方法来测量拓绝缘器约瑟夫森连接处的磁场依赖电流相位关系. 这种技术揭示了非相互传输和可调节的约瑟夫森二极管效应,但没有发现Majorana绑定状态的证据.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子技术 量子技术 是一个量子技术.
- 材料科学 材料科学 材料科学
背景情况:
- 约瑟夫森连接 (JJs) 对超导量子技术和寻找像马约拉纳束状态 (MBS) 这样的奇特准粒子至关重要.
- 基于拓绝缘体 (TI) 的JJ提供了一个研究非传统现象的平台,包括非互惠运输.
- 在这些JJ中测量电流相位关系 (CPR) 作为磁场的函数以前没有被探索过.
研究的目的:
- 在基于平面TI的JJ中开发和演示一个基于现场的CPR测量平台.
- 调查这些设备中的非传统效应,如非相互传输和约瑟夫森二极管效应.
- 在磁场下的基于TI的JJ中探测Majorana绑定状态 (MBS) 的存在.
主要方法:
- 使用NbSe2和几层Bi2Se3.3制造平面的约瑟夫森连接点.
- 测量电流相位关系 (CPR) 作为应用磁流的函数.
- 分析超级电流分布及其对设备特征的影响.
主要成果:
- 当流量量子线程连接时,观察到异常的峰值浸泡CPR结构和非互惠的超流流.
- 证明了强大的和可调节的约瑟夫森二极管效应,归因于不均的超级电流分布.
- 在研究的基于TI的JJ中没有发现Majorana绑定状态 (MBS) 的证据.
结论:
- 磁场依赖的CPR测量是探测基于TI的超导器件的强大工具.
- 该研究提供了对TI JJs中非互惠运输和约瑟夫森二极管效应的见解.
- 提供了开发非互惠超导电子的设计策略,并强调需要对MBS进行进一步调查.
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