近日，西湖大学的林效&吴从军及其研究小组与北京理工大学的王秩伟等人合作并取得一项新进展。经过不懈努力，他们揭示笼目CsV₃Sb₅超导二极管效应及干涉图样。相关研究成果已于2024年5月15日在国际权威学术期刊《自然》上发表。

该研究团队报道了在本征CsV₃Sb₅薄片中具有边界超电流的动态超导域的观测结果。研究人员在热化历史调制极性的情况下观察到无磁场超导二极管效应，表明在自发时间反演对称破缺背景下存在动态超导有序域。在外加磁场作用下，临界电流表现出双缝超导干涉模式。图样的特性是通过热循环调制的。

这些现象是由周期性调制的超电流沿特定磁通量子化约束的域边界流动所导致的。 这一研究不仅揭示了CsV₃Sb₅薄片中的新颖超导序，还为研究人员在这个有趣的拓扑笼目系统中探索奇异物理现象（如马约拉纳零模式）提供了可能的方向。

据悉，阻挫晶格几何、非平凡带拓扑和关联之间的相互作用产生了笼目系统中丰富的物质量子态。该家族的一系列新成员AV₃Sb₅ (A=K, Rb或Cs)表现出一系列对称破缺相变，涉及3Q手性电荷有序，电子向列性，旋子对密度波和超导性。超导序的性质尚待进一步研究和解决。

附：英文原文

Title: Superconducting diode effect and interference patterns in kagome CsV₃Sb₅

Author: Le, Tian, Pan, Zhiming, Xu, Zhuokai, Liu, Jinjin, Wang, Jialu, Lou, Zhefeng, Yang, Xiaohui, Wang, Zhiwei, Yao, Yugui, Wu, Congjun, Lin, Xiao

Issue&Volume: 2024-05-15

Abstract: The interplay among frustrated lattice geometry, non-trivial band topology and correlation yields rich quantum states of matter in kagome systems. A series of recent members in this family, AV₃Sb₅ (A=K, Rb or Cs), exhibit a cascade of symmetry-breaking transitions, involving the 3Q chiral charge ordering, electronic nematicity, roton pair density wave and superconductivity. The nature of the superconducting order is yet to be resolved. Here we report an indication of dynamic superconducting domains with boundary supercurrents in intrinsic CsV₃Sb₅ flakes. The magnetic field-free superconducting diode effect is observed with polarity modulated by thermal histories, suggesting that there are dynamic superconducting order domains in a spontaneous time-reversal symmetry-breaking background. Strikingly, the critical current exhibits double-slit superconductivity interference patterns when subjected to an external magnetic field. The characteristics of the patterns are modulated by thermal cycling. These phenomena are proposed as a consequence of periodically modulated supercurrents flowing along certain domain boundaries constrained by fluxoid quantization. Our results imply a time-reversal symmetry-breaking superconducting order, opening a potential for exploring exotic physics, for example, Majorana zero modes, in this intriguing topological kagome system.

DOI: 10.1038/s41586-024-07431-y

Source: https://www.nature.com/articles/s41586-024-07431-y