AI 中文总结
该研究利用杂质束缚态光谱研究最优掺杂RbV₃Sb₅，发现其超导态为全能隙且具双能量尺度，证明其非常规手性超导性，确立了该光谱技术作为笼目材料超导的相位敏感探针。
AI 中文摘要
笼目金属的超导配对对称性仍是核心未解决问题，很大程度上是因为能够区分不同可能序参量的相位敏感实验难以开展。光谱成像扫描隧道显微镜测量的杂质束缚态的空间和能量特征编码了超导序参量的信息。此处，我们使用杂质束缚态光谱研究最优掺杂的RbV₃Sb₅，其中电荷密度波不稳定性被完全抑制。我们发现超导态是全能隙的，且呈现两个不同的能量尺度，与多带序参量一致。非磁性缺陷周围的原子级光谱显示出明显的粒子-空穴不对称束缚态。与理论计算的比较表明，这些束缚态与常规s波和符号改变的s±配对不兼容。我们的计算还显示，数据与手性序参量完全一致。我们的结果确立了杂质束缚态光谱作为笼目材料中超导性的强大相位敏感探针，并提供了强有力的证据，证明最优掺杂的RbV₃Sb₅实现了全能隙手性超导态。
英文摘要
The superconducting pairing symmetry of kagome metals remains a central unresolved question largely because phase-sensitive experiments capable of distinguishing between different possible order parameters have been difficult to implement. The spatial and energetic characteristics of impurity bound states measured by spectroscopic-imaging scanning tunneling microscopy encode information on the superconducting order parameter. Here, we use impurity-bound state spectroscopy to investigate optimally doped RbV$_3$Sb$_{5}$ where the charge-density wave instability is fully suppressed. We find that the superconducting state is fully gapped and exhibits two distinct energy scales, consistent with a multiband order parameter. Atomic-scale spectroscopy around nonmagnetic defects reveals pronounced particle-hole asymmetric bound states. Comparison with theoretical calculations demonstrates that these bound states are incompatible with conventional $s$-wave and sign-changing $s^{\pm}$ pairing. Our calculations also show that the data are fully consistent with a chiral order parameter. Our results establish impurity-bound-state spectroscopy as a powerful phase-sensitive probe of superconductivity in kagome materials and provide strong evidence that optimally doped RbV$_3$Sb$_{5}$ realizes a fully gapped chiral superconducting state.
