电子到空穴掺杂BaFe2As2铁基超导体系的电子拉曼散射实验研究

项目名称： 电子到空穴掺杂BaFe2As2铁基超导体系的电子拉曼散射实验研究

项目编号： No.11474357

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 张清明

作者单位： 中国科学院物理研究所

项目金额： 98万元

中文摘要： 铁基超导体是继铜氧化物高温超导体发现后凝聚态物理领域又一重大进展，它具有仅次于铜氧化物超导体的高转变温度和良好的金属延展性，蕴涵着重大的基础研究价值和应用潜力。本申请书采用低温强磁场高压拉曼散射系统，同时与变温和同步辐射X-射线衍射、物理性能测量系统（PPMS）和超导量子干涉仪（SQUID-VSM）等结构、输运和磁性测量手段配合，以BaFe2As2（122）体系为代表，拟对从电子掺杂到空穴掺杂的系列高质量单晶，进行系统的电子拉曼散射研究，获得超导能隙、电声子耦合和反铁磁波动从电子到空穴掺杂的系统演化行为，总结演化规律，分析可能的配对对称性，基于上述系统的测量数据尝试建立自洽的铁基超导中电子、声子、磁子等元激发相互作用的图像，为理解铁基超导机理和探索相关的新型超导体提供实验参考依据。

中文关键词： 铁基超导体；电子拉曼散射；超导能隙；配对对称性；电声子耦合

英文摘要： The discovery of iron-based superconductors has made a great breakthrough in condensed matter physics after cuprate superconductors. The iron-based superconducting family has the second highest transtion temperature and exhibits good malleability. It means that iron-based superconductors are enormously valuable in both fundamental research and potential industrial applications. In this project, we plan to carry out a comprehensive electronic Raman scattering study on electron and hole-doped high-quality iron-based superconductors repsented by BaFe2As2 system (122). We will employ two state-of-art Raman scattering facilities with low temperatures, high magnetic fields and high pressure, and other structural, transport and megnetic characterization methods such as temperature-variable and/or synchrotron x-ray diffraction, physical property measurement system (PPMS) and superconducting quantum interference devices (SQUID-VSM). We will be able to obtain key imformation on superconducting gap, electron-phonon coupling and antiferromagnetic fluctuations and their evolutions from electron to hole doping.The key parameters and their evolutions can help us to understand possible pairing symmetries. The systematic measurements will allow us to establish a self-consistent piture of the interactions between electrons, phonons, magnons and other elementry excitations in iron-based supercondutors, which may shed light into superconducting mechanism and offer substantial experimental evidences and/or clues for exploring relevant new-type superconductors.

英文关键词： Iron-based superconductors;Electronic Raman scattering;Superconducting gap;Pairing symmetry;electron-phonon coupling