二维极限下晶体薄膜的超导特性

In recent years，with the development of single crystalline thin films fabrication technique, the superconductivity at two dimensional (2D) limit in crystalline samples has become a new frontier in condensed matter physics. The 2D limit means that the superconducting films are around one atomic or unit cell thick. This project focuses on the superconductivity of high quality single crystalline superconducting films at 2D limit grown by MBE. The main contents of the research include 1) Fabrication and superconductivity of high temperature superconducting films and metal films at 2D limit; 2) the quantum Griffiths singularity and quantum phase transition in 2D superconductors; 3) seeking for topological superconductivity in 2D films. The applicant has made significant achievements in previous studies. Thus, with the support of this project, the applicant's research group will deeply explore the fabrication technique of single crystalline superconducting films at 2D limit, and investigate on the important scientific problems, such as quantum phase transition and topological superconductivity. The remarkable progress in this direction can be expected.

近年来随着晶体薄膜制备技术的发展，二维极限下晶体薄膜的超导已成为凝聚态物理领域的新兴前沿方向。所谓二维极限，指研究对象为单原子或单原胞级厚度的超导薄膜。本项目主要利用超高真空MBE-STM联合系统，通过优化选取薄膜与衬底材料外延生长高质量的性质可控的原子级厚度的超导薄膜，探寻新的二维超导体，并结合低温强磁场电输运测量，深入研究二维极限下的超导特性。研究的主要内容包括：1）二维极限下高温超导薄膜与金属单质薄膜的制备与物性；2）二维超导的量子Griffiths奇异性与量子相变；3）二维晶体中拓扑超导的探索。申请人在与项目相关的前期工作中已做出具有国际影响力的重要成果。在项目支持下，申请人将拓展二维极限下的晶体超导薄膜的制备工艺，深入探索量子相变和拓扑超导等物理领域的重要科学问题，以期取得重要突破。

近年来随着晶体薄膜制备技术的发展，二维极限下晶体薄膜的超导已成为凝聚态物理领域的新兴前沿方向。本项目主要利用超高真空MBE-STM联合系统等，通过优化选取薄膜与衬底材料外延生长高质量的性质可控的原子级厚度的超导薄膜，探寻新的二维超导体，并结合低温强磁场电输运测量，深入研究二维极限下的超导特性。研究的主要结果包括：1）高温超导体系中二维反常金属态的证实；2）二维高温超导体中的马约拉纳零能模证据；3）单层铁基超导薄膜中马约拉纳束缚态的发现；4）二维晶态超导体系中反常量子格里菲斯奇异性的发现；5）单层FeSe中库珀配对的谱学探测；6）二维晶态超导体中的第二类伊辛超导与反常金属态；7）二维晶态超导体中的平行场量子格里菲斯奇异性；8）微纳尺度伊辛超导器件中的非本征和本征反常金属态。