Effect of electron count and chemical complexity in the Ta-Nb-Hf-Zr-Ti high-entropy alloy superconductor
Effect of electron count and chemical complexity in the Ta-Nb-Hf-Zr-Ti high-entropy alloy superconductor
复制标题
DOI：
10.1073/pnas.1615926113
复制
发表时间：
2016-11-15
影响因子：
11.1
通讯作者：
Cava, Robert Joseph
中科院分区：
文献类型：
--
作者：
von Rohr, Fabian;Winiarski, Michal J.;Cava, Robert Joseph
高熵合金是由简单晶格上的主元素随机混合而成，并由高混合熵稳定。最近发现的体心立方(BCC)Ta-Nb-Hf-Zr-Ti高熵合金超导体似乎既表现出简单的晶态金属间化合物的性质，又表现出非晶态材料的性质；例如，它具有明确的超导转变以及对无序的特殊的稳健性。我们证明了高熵合金超导转变温度的价电子数依赖关系介于类似的简单固溶体和非晶态材料之间，并测试了合金复杂性对超导电性的影响。当超导电性在晶态和非晶态材料之间演化时，我们建议将高熵合金作为研究超导电性的优秀中间体系。
High-entropy alloys are made from random mixtures of principal elements on simple lattices, stabilized by a high mixing entropy. The recently discovered body-centered cubic (BCC) Ta-Nb-Hf-Zr-Ti high-entropy alloy superconductor appears to display properties of both simple crystalline intermetallics and amorphousmaterials; e.g., it has a well-defined superconducting transition along with an exceptional robustness against disorder. Here we show that the valence electron count dependence of the superconducting transition temperature in the high-entropy alloy falls between those of analogous simple solid solutions and amorphous materials and test the effect of alloy complexity on the superconductivity. We propose high-entropy alloys as excellent intermediate systems for studying superconductivity as it evolves between crystalline and amorphous materials.