AI 中文总结
研究人员在无任何异质结构的NbSe2薄片中，通过压力诱导实现了无需显式打破时间反演对称性的无磁场超导二极管效应，确立了压力工程在相关超导器件设计中的应用价值。
AI 中文摘要
超导二极管效应（SDE）是一种引人入胜的非互易现象，即临界电流在相反电流方向上存在差异。人们普遍认为，实现SDE需要同时打破反演对称性（IS）和时间反演对称性（TRS），这通常通过异质结构工程和施加外磁场来实现。本文中，我们报道了在无任何异质结构的NbSe2薄片中，压力诱导的无磁场SDE。我们通过二次谐波生成证实，仅压力即可打破IS。关键的是，施加面外磁场（B）时，SDE表现出关于B的偶性行为，这意味着不存在显式的TRS打破。这一发现挑战了主流理论范式，表明无需显式打破TRS即可出现无磁场SDE。因此，我们的工作确立了压力工程作为诱导非互易超导电性、设计多功能无磁场超导器件的强大工具。
英文摘要
The superconducting diode effect (SDE) is a fascinating nonreciprocal phenomenon where the critical current is different for opposite current directions. It is widely believed that realizing SDE requires breaking both inversion symmetry (IS) and time-reversal symmetry (TRS), which are usually achieved via heterostructure engineering and applying external magnetic fields. Here, we report a pressure-induced magnetic-field-free SDE in NbSe2 flakes without any heterostructures. We show that pressure alone breaks the IS, as confirmed by the second harmonic generation. Crucially, upon applying an out-of-plane magnetic field (B), the SDE exhibits even-in-B behavior, implying the absence of explicit TRS breaking. This finding challenges the prevailing theoretical paradigm and demonstrates that a magnetic-field-free SDE can emerge without explicitly breaking TRS. Thereby, our work establishes pressure engineering as a powerful tool for inducing nonreciprocal superconductivity and designing versatile, magnetic-field-free superconducting devices.
Comments10 pages,4 figues
Journal refPhys. Rev. Lett. 2026
