Electron selfenergy in the superconducting pnictides:orbital dependence, anisotropy, temperature dependence and its relation with the phase diagram

超导磷族元素中的电子自能：轨道依赖性、各向异性、温度依赖性及其与相图的关系

• 批准号: 168211202
• 负责人: Professor Dr. Carsten Honerkamp
• 金额: --
• 依托单位: Institut für Theoretische Festkörperphysik C
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/168211202?language=en
• 关键词: Electron; selfenergy; superconducting; pnictides; orbital

This project aims at a theoretical description of the electronic self-energy due to short-ranged electron-electron interactions in multi-band models for the iron pnictide superconductors. The primary objects of interest are the wave-vector, orbital/ band and temperature dependences of the normal-state self-energy around the various Fermi pockets. The orbital dependence of the self-energy has a direct influence on the predicted superconducting gap structure around the Fermi pockets and hence on the whole phase diagram. Its inclusion is therefore an important step to assure the predictive power of the weak-coupling theory for the gap structure. Furthermore, motivated by experimental trends in the resistivity, the relation of possible non-Fermi-liquid-like components in the imaginary part of the self-energy to the critical temperature for superconductivity, Tc, or other phase transition lines, will be investigated. Here, besides the trends as a function of doping, the evolution of the self-energies and Tcs as a function of pressure will be computed as a cross check. The goals are the comparison with the experimental findings for the relation between resistivity and Tc and to predict experimental signatures that can be used to discriminate between different theoretical ideas for the superconducting pairing. The main theoretical method used is the functional renormalization group, but other techniques like the random phase approximation and Boltzmann transport equations may be used as well for further modelling and comparison.

本计画的目的是在多能带模型中，对铁磷属元素化物超导体中，由短程电子-电子相互作用所引起的电子自能进行理论描述。感兴趣的主要对象是波矢量，轨道/带和温度依赖的正常状态的自能周围的各种费米口袋。自能的轨道依赖性对费米口袋周围的超导能隙结构有直接的影响，从而对整个相图。因此，它的列入是一个重要的步骤，以确保弱耦合理论的预测能力的差距结构。此外，在电阻率的实验趋势的激励下，可能的非费米液体的自能的虚部的成分的超导临界温度，Tc，或其他相变线的关系，将被调查。这里，除了作为掺杂的函数的趋势之外，作为压力的函数的自能和Tcs的演变将被计算为交叉检查。我们的目标是与电阻率和Tc之间的关系的实验结果进行比较，并预测实验签名，可用于区分不同的理论思想的超导配对。所使用的主要理论方法是泛函重整化群，但也可以使用其他技术，如随机相位近似和玻尔兹曼输运方程，以进一步建模和比较。