Abstract The superconducting properties of the intermetallic compound NiBi3 have been studied mostly in bulk crystals. In this report we have studied several aspects of NiBi3 thin films, spontaneously formed at the interface of Ni and Bi multilayers. We have observed superconducting transition around 3.9 K, close to the bulk transition temperature of 4.1 K. Due to the diffusive mechanism of formation of NiBi3, additional phenomena such as magnetic (Nickel) impurity induced Kondo effect and self organized Turing pattern formation also come into picture. From X-ray diffraction and Magneto-resistance measurements we have established the presence of atomic Ni impurities in the films. Kondo minima were found to scale with varied concentration of Ni impurities in a series of Ni-Bi multilayer films (with fixed Ni thickness and varied Bi thickness). Similarly, saturation magnetization and superconducting transition temperature were also found to follow the concentration of Ni impurities. In addition, we have also observed signatures of Turing patterns, from magnetic force microscopy, naturally formed with time without any external heat treatment.

中文翻译：

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超导性、近藤效应和金属间化合物 NiBi 3 薄膜中自组织图案形成的观察

摘要 金属间化合物NiBi3的超导性质主要在块状晶体中进行研究。在本报告中，我们研究了 NiBi3 薄膜的几个方面，这些薄膜在 Ni 和 Bi 多层膜的界面处自发形成。我们已经观察到 3.9 K 附近的超导转变，接近 4.1 K 的体相转变温度。 由于 NiBi3 形成的扩散机制，磁性（镍）杂质诱导的近藤效应和自组织图灵图案形成等其他现象也开始出现图片。通过 X 射线衍射和磁阻测量，我们已经确定薄膜中存在原子 Ni 杂质。发现 Kondo 最小值随着一系列 Ni-Bi 多层膜（具有固定的 Ni 厚度和不同的 Bi 厚度）中的 Ni 杂质浓度的变化而变化。类似地，还发现饱和磁化强度和超导转变温度跟随 Ni 杂质的浓度。此外，我们还通过磁力显微镜观察到了图灵模式的特征，这些特征是随时间自然形成的，无需任何外部热处理。