AI 中文总结
研究具有 Kagome 晶格的 ScIr₂₋ₓSiₓ 家族的非常规超导性，结合μ子自旋光谱测量与能带结构计算，发现其超导配对可用双能隙模型描述，因能隙有节点表明是非常规超导，独特平带致强关联，该家族性质使其成为相关研究的有趣系统。
AI 中文摘要
具有 Kagome 晶格的材料承载着由能带拓扑、自旋轨道耦合、磁性和电子关联相互作用驱动的奇异量子现象。尽管 Kagome 材料的磁性已被广泛研究，但由于合适材料有限，其非常规超导性仍很大程度未被探索。本文通过将μ子自旋光谱测量与能带结构计算相结合，报告了 ScIr₂₋ₓSiₓ 家族中非常规超导性的证据。母体 ScIr₂ 经历从高温立方相到低温菱面体相的结构相变，Ir Kagome 层虽有轻微畸变但仍保留。Si 替代抑制了结构相变，但 ScIr₂₋ₓSiₓ 的超导配对仍可用双能隙模型很好地描述。由于至少一个能隙有节点，表明是非常规超导。其非常规性质可由费米能级附近出现的独特平带解释，导致 ScIr₂₋ₓSiₓ 家族中强电子关联。此外，ScIr₂ 的低温相表现出 Ir 手性链，可归类为拓扑手性晶体。总体而言，ScIr₂₋ₓSiₓ 家族的异常性质使其成为研究非常规超导、平带和手性之间相互作用的有趣但罕见的系统。
英文摘要
Materials with a kagome lattice host exotic quantum phenomena driven by the interplay between band topology, spin-orbit coupling, magnetism, and electronic correlations. While magnetism of kagome materials has been widely investigated, their unconventional superconductivity (SC) remains largely unexplored due to the limited availability of suitable materials. Here, we report evidence of unconventional SC in the ScIr$_{2-x}$Si$_{x}$ family by combining muon-spin spectroscopy measurements with band-structure calculations. The parent ScIr$_2$ undergoes a structural phase transition from a high-$T$ cubic- to a low-$T$ rhombohedral phase, while the Ir kagome layer remains, albeit slightly distorted. Although the structural transition is suppressed by Si substitution, the superconducting pairing of ScIr$_{2-x}$Si$_{x}$ remains well described by a two-gap model. Since at least one of the gaps has nodes, this indicates an unconventional SC. Its unconventional nature can be explained by the distinct flat bands occurring near the Fermi level, leading to strong electronic correlations in the ScIr$_{2-x}$Si$_{x}$ family. Moreover, the low-$T$ phase of ScIr$_2$ exhibits an Ir chiral chain; therefore, it can be classified as a topological chiral crystal. Overall, the unusual properties of the ScIr$_{2-x}$Si$_{x}$ family make it an interesting, albeit rare, system for studying the interplay between unconventional SC, flat bands, and chirality.
Comments24 pages, 7 figures; accepted by Adv. Mater
