New approaches to iron-based superconductors

2008年，发现了一系列新的高温超导体，其中含有砷化铁、磷化铁或硒化铁层，在过去的两年里，主要的研究工作试图理解这一现象。新的超导体产生了巨大的兴趣，因为它们在制造用于高场应用的超导磁体和制造用于某些电信和电子设备的上级部件中是重要的。新超导体的发现，特别是那些表现出非常规行为且不符合巴丁-库珀-施里弗模型的超导体的发现，提供了在接近环境温度下实现超导的可能性，是未来可能产生重要技术回报的蓝天研究的一个例子。在这一领域的研究表明，具有相似结构特征的几种化合物表现出超导性，但基本的测量已经探测了这些化合物中的一小部分-那些最适合晶体生长的化合物。虽然大多数小组一直专注于现有的化合物，但在这一领域取得实质性进展的最直接途径是通过创新材料的发现，我们独特的策略包括尝试合成具有砷化铁或硒化铁层的新型化合物，这些化合物可能具有迄今为止发现的材料的上级性能。特别是，我们的重点是使用低温合成来获得在高温下不稳定的组合物。这有望为这些超导体的研究揭开新的篇章。合成将与实验室和国际设施中的物理性质测量平行进行，这对于理解这些化合物中的超导性和磁性如何与组成和晶体结构相关非常重要。这些结果将反馈到综合方案中。新化合物的样品将提供给社区的其他成员，他们的专业知识是专门测量物理特性。最终，这项研究可能会产生新的超导材料，这些材料中的成分，晶体结构和物理性质之间的相关性，并为这些材料超导的原因提供基本见解，可能为非常规超导现象的预测性理论处理铺平道路。

In 2008 a new series of high temperature superconductors containing iron arsenide, phosphide or selenide layers was discovered and in the last 2 years major research efforts have attempted to understand the phenomenon. New superconductors generate enormous interest as they are important in the manufacture of superconducting magnets for high field applications and in the manufacture of superior components for certain telecommunications and electronic devices. The discovery of new superconductors, particularly those which exhibit unconventional behaviour and do not conform to the Bardeen-Cooper-Schrieffer model, offers the possibility of superconductivity at temperatures approaching ambient and is an example of blue-skies research which may have an important technological payoff in the future. The research in this area has shown that several compounds with similar structural features exhibit superconductivity, but the fundamental measurements have probed a rather small number of these compounds - those which are most amenable to crystal growth. While most groups have been focused on existing compounds, the most direct route to substantial progress in this area is via innovative materials discovery and our unique strategy includes an attempt to synthesise new classes of compound with iron arsenide or iron selenide layers which may have superior properties to the materials discovered thus far. In particular our focus is on using low temperature synthesis to access compositions which are not thermodynamically stable at high temperatures. This is expected to open a new chapter in the study of these superconductors. The synthesis will be carried out in parallel with physical property measurements in the laboratory and at international facilities which will be important for understanding how the superconductivity and magnetism in these compounds is correlated with composition and crystal structure. These results will be fed back into the synthetic programme. Samples of the new compounds will be made available to other members of the community whose expertise is in specialised measurements of physical properties. Ultimately the research may yield new superconducting materials, correlations between composition, crystal structure and physical properties in these materials, and also offer fundamental insights into why these materials superconduct, possibly paving the way for predictive theoretical treatments of the phenomenon of unconventional superconductivity .