Raman study of the interrelation of electron dynamics and phase transitions iron-based compounds

铁化合物定义了一类超导转变温度高于50 K的新材料。我们建议用带和动量选择的电子拉曼散射来研究它们的电子性质和相关化合物的电子性质随温度、外加磁场和压力的变化。与SPP1458优先项目的合作伙伴合作，我们计划使用现象学和微观模型来解释光散射结果。重点将放在超导能隙的研究上。根据目前的理解，间隙的动量和掺杂依赖性对于发现和测试模型至关重要。提出的研究目的是提高对导致自旋有序和超导性的相互作用的理解。除此之外，我们计划分析这些现象之间的相互关系，并与晶格解决为什么高温超导总是发生在自旋或电荷顺序附近的问题。沿着这些推理路线，与理论家、化学家和材料科学家的密切合作旨在改进现有系统和开发新系统。

The iron pnictides define a new material class with superconducting transition temperatures above 50 K. We propose to study their electronic properties and those of related compounds as a function of temperature, applied magnetic field and pressure with band- and momentum-selective electronic Raman scattering. In collaboration with partners in the Priority Program SPP1458 we plan to interpret the light scattering results using phenomenological and microscopic models. Specific emphasis will be placed on the study of the superconducting energy gap. According to the present understanding, the momentum and doping dependence of the gap is of pivotal importance for finding and testing models. The objective of the proposed research is an improved understanding of the interactions leading to spin order and superconductivity. Beyond that we plan to analyze the interrelation of these phenomena among each other and with the lattice addressing the question of why high-temperature superconductivity occurs always in the proximity of spin or charge order. Along these lines of reasoning, the close collaboration with theorists, chemists, and material scientists is intended to aim at the improvement of existing and the development of new systems.