论文标题
基于各向异性铁的化合物RBCA2FE4AS4F2中的节点多图超导性
Nodal multigap superconductivity in the anisotropic iron-based compound RbCa2Fe4As4F2
论文作者
论文摘要
12442种化合物是最近发现的铁基超导体家族，由于其强烈的各向异性结构，它们与铜矿具有多个特征，但迄今为止鲜为人知。在这里，我们报告了RBCA2（FE1-XNIX）4AS4F2单晶的间隙结构和各向异性，该晶体通过定向点接触的Andreev-Reflection频谱和Coplanar波导谐振器测量结果进行了研究。鉴定了两个间隙，并具有d-wave样淋巴结结构的明确特征，这些结构持续存在于ni掺杂，由带有对称性淋巴结的两个波段D-d状态很好地描述。揭示了伦敦较大的穿透深度各向异性，弱取决于温度，并且与D-D模型完全兼容。
The 12442 compounds are a recently discovered family of iron-based superconductors, that share several features with the cuprates due to their strongly anisotropic structure, but are so far poorly understood. Here, we report on the gap structure and anisotropy of RbCa2(Fe1-xNix)4As4F2 single crystals, investigated by a combination of directional point-contact Andreev-reflection spectroscopy and coplanar waveguide resonator measurements. Two gaps were identified, with clear signatures of d-wave-like nodal structures which persist upon Ni doping, well described by a two-band d-d state with symmetry-imposed nodes. A large London penetration depth anisotropy was revealed, weakly dependent on temperature and fully compatible with the d-d model.
